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SMITHSONIAN CONTRIBUTIONS TO PALEOBIOLOGY • NUMBER 21

Permian Brachiopods of West Texas, IV

(PART 2–PLATES)

G. Arthur Cooper
and Richard E. Grant

SMITHSONIAN INSTITUTION PRESS

City of Washington

1976

Contents

PLATES

503. Petasmatherus and Tricoria

504. Elassonia, Leiorhynchoidea, Aphaurosia, and Paranorella

505. Ptygmactrum and Fascicosta

506. Trophisina

507. Chaeniorhynchus, Deltarina, and Tricoria

508. Pontisia, Strigirhynchia, Deltarina, Bryorhynchus, Phrenophoria, Chaeniorhynchus, Lirellaria, Ptilotorhynchus, and Cenorhynchia

509. Divaricosta, Fascicosta, and Allorhynchus

510. Strigirhynchia, Paranorella, Pontisia, Cenorhynchia, Bryorhynchus, Anteridocus, and Cleiothyridina

511. Lirellaria and Aphaurosia

512. Amphipella and Acolosia

513. Ptilotorhynchus, Iotina, Acolosia, and Madarosia

514. Strigirhynchia and Phrenophoria

515. Cenorhynchia, Acolosia?, Aphaurosia, Wellerella, Anteridocus, Phrenophoria, Pontisia, and Tautosia

516. Pontisia and Phrenophoria

517. Antronaria, Anteridocus, Cenorhynchia, Phrenophoria, Pontisia, and Madarosia

518. Phrenophoria

519. Phrenophoria, Tautosia, Cenorhynchia, and Holosia

520. Cenorhynchia, Pontisia, Leiorhynchoidea, Anteridocus, Strigirhynchia, and Ptygmactrum

521. Phrenophoria, Petasmatherus, Tautosia, Fascicosta, Anteridocus, Aphaurosia, Cenorhynchia, and Strigirhynchia

522. Phrenophoria

523. Phrenophoria, Holosia, and Tautosia

524. Tautosia and Phrenophoria

525. Tautosia, Phrenophoria, and Acolosia

526. Tautosia

527. Tautosia and Wellerella

528. Wellerella

529. Anteridocus, Pontisia, and Antronaria

530. Antronaria and Pontisia

531. Antronaria and Pontisia

532. Antronaria

533. Antronaria and Pontisia

534. Anteridocus and Pontisia

535. Anteridocus, Antronaria, and Pontisia

536. Antronaria and Pontisia

537. Antronaria

538. Antronaria and Anteridocus

539. Hemileurus and Anteridocus

540. Anteridocus, Petasmatherus, and Allorhynchus

541. Allorhynchus, Petasmatherus, and Phrenophoria

542. Allorhynchus

543. Allorhynchus and Cenorhynchia

544. Cenorhynchia and Tautosia

545. Cenorhynchia

546. Cenorhynchia and Bryorhynchus

547. Cenorhynchia and Bryorhynchus

548. Bryorhynchus, Leiorhynchoidea, and Madarosia

549. Leiorhynchoidea

550. Leiorhynchoidea and Bryorhynchus

551. Paranorella, Petasmatherus, and Anteridocus

552. Aphaurosia, Divaricosta, Cenorhynchia, Pontisia, Ptilotorhynchus, Phrenophoria, Deltarina, Antronaria, Fascicosta, and Madarosia

553. Phrenophoria, Stenoscisma, Wellerella, and Tautosia

554. Stenoscisma

555. Stenoscisma

556. Stenoscisma

557. Stenoscisma

558. Stenoscisma

559. Stenoscisma

560. Stenoscisma

561. Stenoscisma

562. Stenoscisma

563. Stenoscisma

564. Stenoscisma

565. Stenoscisma

566. Stenoscisma

567. Stenoscisma

568. Stenoscisma

569. Stenoscisma

570. Stenoscisma

571. Stenoscisma

572. Stenoscisma

573. Stenoscisma

574. Stenoscisma

575. Stenoscisma

576. Stenoscisma

577. Stenoscisma

578. Stenoscisma

579. Stenoscisma

580. Stenoscisma

581. Stenoscisma

582. Stenoscisma

583. Stenoscisma

584. Torynechus

585. Torynechus

586. Psilocamara and Torynechus

587. Xenosaria, Crurithyris, and Grandaurispina

588. Crurithyris

589. Crurithyris

590. Crurithyris and Attenuatella

591. Gypospirifer

592. Gypospirifer and Neospirifer

593. Neospirifer and Gypospirifer

594. Neospirifer

595. Neospirifer

596. Neospirifer

597. Neospirifer

598. Neospirifer

599. Neospirifer

600. Neospirifer

601. Neospirifer and Gypospirifer

602. Neospirifer and Gypospirifer

603. Neospirifer

604. Neospirifer

605. Neospirifer

606. Neospirifer

607. Neospirifer

608. Neospirifer

609. Neospirifer

610. Neospirifer

611. Neospirifer

612. Neospirifer

613. Cartorhium

614. Cartorhium

615. Cartorhium

616. Cartorhium

617. Cartorhium

618. Cartorhium

619. Cartorhium

620. Cartorhium

621. Lepidospirifer

622. Lepidospirifer

623. Lepidospirifer

624. Cartorhium and Lepidospirifer

625. Spiriferinaella

626. Spiriferinaella, Eridmatus, and Spiriferella

627. Spiriferella

628. Spiriferella

629. Spiriferella

630. Spiriferella

631. Spiriferella and Martinia

632. Eliva

633. Elivina, Rallacosta, and Eliva

634. Elivina

635. Neophricadothyris

636. Neophricadothyris

637. Neophricadothyris

638. Neophricadothyris

639. Neophricadothyris

640. Anomaloria

641. Astegosia

642. Astegosia

643. Martinia

644. Martinia

645. Martinia

646. Rallacosta and Heteraria

647. Rallacosta

648. Rallacosta

649. Martinia, Neophricadothyris, Astegosia, and Anomaloria

650. Cleiothyridina

651. Cleiothyridina and Nucleospira

652. Composita

653. Composita

654. Composita

655. Composita

656. Composita

657. Composita

658. Composita

659. Composita

660. Composita

661. Composita

662. Composita

Publication in Smithsonian Contributions to Paleobiology

PLATES 503–662

PLATE 503

Petasmatherus and Tricoria

Petasmatherus opulus, Cooper and Grant: 1, Anterior, posterior, side, ventral, and dorsal views of a complete specimen, ×2, hypotype USNM 148307c. [Word Formation (China Tank Member), USNM 706c.]

2, Anterior, dorsal, posterior, ventral, side, and dorsal views of complete specimen, ×2, (dorsal. ×1), hypotype USNM 148302f. [Word Formation (Willis Ranch Member), USNM 706.]

3, Anterior, dorsal, ×1, posterior, ventral, side, and dorsal views of complete specimen, ×2, hypotype USNM 154609. [Cherry Canyon Formation (Getaway Member), AMNH 496.]

4, Dorsal, anterior, side, posterior, and ventral views, ×2, and dorsal view, ×1, paratype USNM 148305b; 5, ventral, anterior, side, posterior, and ventral views, ×2, and dorsal view, ×1, holotype USNM 148305a; 6, specimen with pediclce beak broken away to show crura, ×3, hypotype USNM 148305g; 7, interior of pedicle valve, showing well developed interarea, ×3, hypotype USNM 148305h; 8, 9, ventral and laterally tilted views of interior, ×3, showing cardinalia, hypotype USNM 148305i; 10, 11, laterally and anteriorly tilted views of preceding specimen, ×6, showing median ridge, cardinalia, and dental plates; 12, 13, anteriorly tilted and ventral views of interior, ×6, showing cardinalia, paratype USNM 148305f; 14, anterior view of cardinalia, ×6, hypotype USNM 148305j; 15, side view, showing crura, ×6, hypotype USNM 148305k; 16, interior of brachial valve, showing cardinalia, ×3, hypotype USNM 148305–1; 17–19, laterally tilted, ×3, ×6, and interior, ×6, views of brachial valve, paratype USNM 148305e; 20, side view, showing crura and interarea, ×6, hypotype USNM 148305m. [Word Formation (lens between Willis Ranch and Appel Ranch members), USNM 706b.]

Petasmatherus recticardinatus, new species: 21, Posterior, anterior, side, ventral, and dorsal views, ×2, of holotype USNM 152824. [Cherry Canyon Formation (Getaway Member), AMNH 512.]

Petasmatherus cf. P. opulus, Cooper and Grant: 22, Posterior, anterior, side, ventral, and dorsal views, ×2, complete specimen USNM 148310. [Road Canyon Formation, USNM 703d.]

Petasmatherus depressus, new species: 23, Posterior, anterior, side, ventral, and dorsal views, ×2, complete holotype USNM 154614. [Road Canyon Formation, USNM 721j.]

Tricoria hirpex, new species: 24–26, Dorsal, posterior, side, anterior, and ventral views of three immature, complete specimens, showing narrow form, ×1, paratypes USNM 148155b, c, d; 27, dorsal, posterior, side, anterior, and ventral views, ×1, of a complete specimen, paratype USNM 148155f; 28, 29, dorsal, posterior, side, anterior, and ventral views, ×1, immature paratypes USNM 148155h, i; 30, dorsal, posterior, side, anterior, and ventral views, ×1, adult paratype USNM 148155j; 31, dorsal, posterior, side, anterior, and ventral views, ×1, adult paratype USNM 148155k (for enlarged views, see Plate 507: figures 69–71); 32–34, anterior, interior, and laterally tilted views, ×2, of a brachial valve, showing cardinalia and median septum, paratype USNM 148155–l; 35, 36, ventral and laterally tilted views of the preceding, ×4, showing the cardinalia in greater detail; 37, interior of ^ pedicle valve, ×1, paratype USNM 148155m; 38, 39, laterally tilted and interior views of specimen with ventral valve partly broken away, showing the cardinalia, ×2, paratype USNM 148155p; 40, 41, same views as preceding, ×4, showing cardinalia in more detail. [Skinner Ranch Formation (base), USNM 705a.]

PLATE 503.—Petasmatherus and Tricoria.

PLATE 504

Elassonia, Leiorhynchoidea, Aphaurosia, and Paranorella

Elassonia micraria, new species: 1, Dorsal views of four specimens, ×1, from left, paratypes USNM 154620a, b, c, and holotype USNM 154620d; 2, 3, dorsal, posterior, side, anterior, and ventral views, ×3, paratypes USNM 154620a, b; 4, 6, dorsal, posterior, side, anterior, and ventral views, ×3, and dorsal view, ×6, paratype USNM 154620c; 5, 7, dorsal, posterior, side, anterior, and ventral views, ×3, and dorsal view, ×6, holotype USNM 154620d; 8, side view showing interarea and crura, ×12, paratype USNM 154620e; 9, anterior view, ×12, showing median ridge and crura, paratype USNM 154620f; 10, interior of pedicle valve, ×12, paratype USNM 154620g; 11, interior of pedicle valve tilted to show dental plates, ×12, paratype USNM 154620h; 12, 13, interior and interior tilted to show cardinalia, ×12, paratype USNM 154620i; 14, interior of brachial valve, ×12, showing long crura, paratype USNM 154620j; 15, 16, interior and interior tilted of ladge brachial valve, ×12, showing long slender crura, paratype USNM 154620k. [Road Canyon Formation, USNM 702c.]

Elassonia petila, new species: 17, ventral, posterior, side, anterior, and dorsal (also ×1) views, ×3, holotype USNM 148255a; 18, ventral, posterior, side, and dorsal (also ×1) views, ×3, paratype USNM 148255b, and brachial and pedicle valve interiors, ×3, paratypes USNM 148255e, f; 19, 20, interior views of brachial and pedicle valves, ×12, paratypes USNM 148255e, f. [Cathedral Mountain Formation, USNM 702.]

Elassonia scitula, new species: 21, Dorsal, posterior, side, anterior, and ventral views, ×3, and dorsal view, ×1, holotype USNM 148261b; 22, Dorsal view of holotype, ×4, 23, dorsal, posterior, side, anterior, and ventral views, ×1, paratype USNM 148261a; 24, dorsal view of the preceding, ×4; 25, interior of pedicle valve, ×12, paratype USNM 148260a; 26, 27, interior of brachial valve showing cardinalia, ×3 and ×12, paratype USNM 148260b; 28, interior of brachial valve, ×12, paratype USNM 148260c. [Cathedral Mountain Formation, USNM 708u.]

Elassonia sobrina, new species: 29, 30, Ventral, posterior, side, anterior, and dorsal views, ×3, dorsal views, ×1, and ×4, of holotype USNM 148251a; 31, dorsal view of small paratype, ×4, USNM 148251b; 32, interior of brachial valve, ×15, paratype USNM 148251d; 33, interior of brachial valve, ×15, paratype USNM 148251e. [Hess Formation (Taylor Ranch Member), USNM 702d.]

Leiorhynchoidea sulcata, new species: 34–36, Dorsal, anterior, and side views of robust specimen, ×1, holotype USNM 155054. [Cherry Canyon Formation (South Wells Member), AMNH 414.]

Aphaurosia rotundata, new species: 37–39, Dorsal, side, and anterior views of complete specimen, ×2, paratype USNM 154509a; 40–42, side, anterior, and dorsal views of complete specimen, ×2, paratype USNM 154509b; 50, ventral, posterior, side, anterior, and dorsal views, ×1, of the preceding; 43–45, side, dorsal, and anterior views of rotund specimen, ×1, paratype USNM 154509c; 46–48, dorsal, side, and anterior views of large complete specimen, ×2, holotype USNM 154509d; 49, ventral, posterior, side, anterior, and dorsal views, ×1, of holotype; 51, dorsal view of specimen minus most of its pedicle valve, showing dorsal side of crura, ×2, paratype USNM 154509e; 52, interior of brachial valve, ×2, paratype USNM 154509f; 53, interior of brachial valve showing cardinalia, ×2, paratype USNM 154509g; 54, interior of pedicle valve, ×2, paratype USNM 154509h. [Bell Canyon Formation (Lamar Member), USNM 728p.]

Paranorella species 5: 55, 56, Interior of brachial valve, ×1, ×3, showing the leiorhynchoid cardinalia and long median septum, figured specimen 152872a; 57, interior of pedicle valve, ×1, figured specimen USNM 152872b; 58, 59, posterior parts of two brachial valves showing hinge plate and median septum, ×2, figured specimens USNM 152872c, d; 60, interior of pedicle valve, ×2, showing short dental plates and teeth, figured specimen USNM 152872e. [Road Canyon Formation, USNM 726d.]

PLATE 504.—Elassonia, Leiorhynchoidea, Aphaurosia, and Paranorella.

PLATE 505

Ptygmactrum and Fascicosta

Ptygmactrum angulatum, new species: 1, 2, Interior of pedicle valve, ×3, ×9, showing teeth, paratype USNM 148316c; 3, dorsal and ventral views, ×3, of a complete specimen, paratype USNM 148316d; 6, ventral, anterior, side, posterior, and dorsal views. ×3, and dorsal view, ×1, paratype USNM 148316a; 7, 8, ventral, anterior, side, posterior, and dorsal views. ×3, dorsal view, ×1, and dorsal view, ×6, paratype USNM 148316b. [Cathedral Mountain Formation, USNM 702b.]

4, 5, Dorsal, anterior, side, and ventral views, ×3, and dorsal view, ×6, paratype USNM 154622; 21–25, ventral, posterior, anterior, side, and dorsal views, ×4, holotype USNM 148317. [Cathedral Mountain Formation, USNM 703bs.]

9, Interior of brachial valve, ×4, showing the cardinalia, paratype USNM 148318. [Cathedral Mountain Formation, USNM 708u.]

Ptygmactrum acutum, new species: 10, Posterior, dorsal, ×1, anterior, dorsal, side, and ventral views, holotype USNM 154623, ×3; 11, dorsal view, ×6, of the holotype, showing spines on costae. [Road Canyon Formation, USNM 720d.]

Fascicosta bella, new species: 12–15, Dorsal view, ×1, and anterior, dorsal, and side views, ×2, holotype USNM 154621. [Bell Canyon Formation (Rader Member), USNM 725g.]

Ptygmactrum depressum, new species: 16, Anterior, dorsal, ×1, posterior, dorsal, side, and ventral views, ×3, paratype USNM 152861. [Road Canyon Formation, USNM 721j.]

17, 18, Anterior, side, posterior, ventral, dorsal, ×1, and dorsal views, ×3, and dorsal view, ×6, holotype USNM 148319. [Road Canyon Formation, USNM 716xa.]

Ptygmactrum mordicum, new species: 19, Anterior, posterior, side, ventral, and dorsal views, ×3, holotype USNM 148315a; 20, interior of the brachial valve, ×6, showing the cardinalia, paratype USNM 148315b. [Cathedral Mountain Formation, USNM 702.]

Ptygmactrum spiculatum, new species: 26, Dorsal view of a complete specimen, ×3, paratype USNM 148323a; 30, interior of a brachial valve, ×6, paratype USNM 148323b. [Word Formation (lens between Willis Ranch and Appel Ranch members), USNM 706b.]

27, 28, Anterior, dorsal, ×1, posterior, ventral, side, and dorsal views, ×3, and dorsal view, ×6, holotype USNM 152862a; 29, interior of the pedicle valve, ×6, paratype USNM 152862b. [Cherry Canyon Formation (Getaway Member), AMNH 512.]

Ptygmactrum extensum, new species: 31–36, Posterior, anterior, ventral, side, and dorsal views, ×4, and dorsal view, ×1, paratype USNM 148321a; 37–42, side, anterior, ventral, dorsal, and posterior views, ×4, and dorsal view, ×1, holotype USNM 148321b; 43, 44, dorsal view, ×1, ×3, of a complete specimen, paratype USNM 148321c (see Plate 520: figures 40–44 for additional enlarged views); 45–47, dorsal view, ×1, and ventral and dorsal views, ×3, of another complete specimen, paratype USNM 148321d; 48, 49, interior of a brachial valve, ×1, ×8, showing cardinalia and median septum, paratype USNM 148321e. [Road Canyon Formation, USNM 703d.]

50, Dorsal view of a complete specimen, ×3, paratype USNM 148320; 51, 52, interior of the pedicle valve, and the same tilted to show the dental plates, ×3, of the preceding specimen; 53, interior of the brachial valve of the same specimen, ×3; 54, 55, interior of the pedicle valve of the preceding specimen, ×9, ×16, showing dental plates, teeth and interarea; 56, 57, interior of the same brachial valve tilted, ×3 and ×9, showing the cardinalia and small median ridge; 58, interior of the same brachial valve showing the cardinalia, ×9. [Road Canyon Formation, USNM 703c.]

PLATE 505.—Ptygmactrum and Fascicosta.

PLATE 506

Trophisina

Trophisina fenaria, new species: 1, 2, Ventral, anterior, side, posterior, and dorsal views of two complete paratypes, ×1, USNM 148242a, b. [Cathedral Mountain Formation, USNM 702-low.]

3, Ventral, posterior, side, anterior, and dorsal views, ×1, of a young adult, paratype USNM 148236j; 4, 5, ventral, anterior, side, posterior, and dorsal views of two triangular, immature individuals, ×1, paratypes USNM 148236f, g (see also figure 9); 6, ventral, anterior, side, posterior, and dorsal veiws of a paratype slightly more mature than the preceding, ×1, USNM 148236i; 8, 20, enlargements, ×5, of the beak region, showing foramen and disjunct deltidial plates, and tilted to show the dental plates, paratype USNM 148236m; 10, series of immature brachial valves, ×4, showing development of the cardinalia, paratypes USNM 148238a–f; 11, dorsal view of an immature complete specimen, ×3, paratype USNM 148236k; 19, interior of an immature pedicle valve, ×3, paratype USNM 148236–l; 23, 24, interior of an immature brachial valve, ×3, ×6, showing the cardinalia and absence of a median ridge, paratype USNM 148236n; 25, 26, interior of a nearly adult brachial valve, ×3, ×6, showing cardinalia and divided hinge plate, paratype USNM 148236o; 28, anterior view of the interior, ×3, showing the long, slender crura, paratype USNM 148236p; 29, ventral view of the complete hinge plate, ×8, paratype USNM 148236q; 36–38, tilted, slightly tilted, and anterior views of a specimen with both valves, ×6, showing the dental plates, cardinalia, median ridge, and hinge plate nearly complete, paratype USNM 148236s; 39, interior of a young adult brachial valve having an incomplete hinge plate, ×3, paratype USNM 148236t. [Cathedral Mountain Formation, USNM 703b.]

7, Ventral, anterior, side, posterior, and dorsal views of a young adult, ×1, paratype USNM 148224a; 9, series of immature individuals, ×3, smallest four are paratypes USNM 154640a–d, last is paratype USNM 148236g (see figure 5); 12–17, dorsal view, ×1, and posterior, side, anterior, dorsal, and ventral views, ×2, of the holotype USNM 148225; 18, interior of immature pedicle and brachial valves, ×3, paratypes USNM 154640e, f; 21, posterior of a specimen from which the brachial valve has been removed, in dorsal view, ×5, showing the underside of a complete hinge plate, paratype USNM 154640g; 22, posterior of a pedicle valve, ×5, showing disjunct deltidial plates, paratype USNM 154640h; 27, posterior of the pedicle valve, ×5, tilted to show disjunct deltidial plates and dental plates, paratype USNM 154640i; 30, interior of an adult brachial valve with fused hinge plate, ×6, paratype USNM 14640j; 31, 32, dorsal and posterior views, ×3, of a brachial valve with hinge plate still divided, ×3, paratype USNM 154640k; 33, anterior view of the preceding specimen, ×6, showing median ridge and long crura; 34, 35, interior of another brachial valve, ×3, showing cardinalia and muscle scars, and the same specimen in posterior view, ×6, showing the nearly complete hinge plate and long crura, paratype USNM 154640–l; 40, anterior view of a specimen with parts of both valves, ×3, showing dental plates and crura, paratype USNM 154640m; 41, another specimen preserved like the preceding, ×3, and showing long crura, paratype USNM 154640n; 42, tilted anterior view of a specimen, ×2, with side broken to show the crura, paratype USNM 154640o. [Cathedral Mountain Formation, USNM 702un.]

PLATE 506.—Trophisina.

PLATE 507

Chaeniorhynchus, Deltarina, and Tricoria

Chaeniorhynchus inauris, new species: 1–5, Ventral, posterior, side, anterior, and dorsal views, ×1, of the holotype USNM 148784a; 6–8, ventral, side, and anterior views, ×2, of the holotype. [Cathedral Mountain Formation, USNM 702-low.]

9–13, Dorsal, posterior, anterior, ventral, and side views of a complete specimen, ×1, paratype USNM 148520a; 14, ventral view of a specimen with beak broken away to show the crura, ×2, paratype USNM 154654a; 15, 16, interior and tilted views of a brachial valve, ×2, showing the hinge plate, paratype USNM 154654c; 17, 18, interior of another brachial valve, ×2, ×4, showing the hinge plate and median septum, paratype USNM 154654b; 19, interior of a young pedicle valve having no deltidial plates, ×2, paratype USNM 154654e; 20, anterior view of the interior, ×6, showing the median septa and crura, paratype USNM 148520b. [Cathedral Mountain Formation, USNM 702.]

Chaeniorhynchus salutare, new species: 21–25, Ventral, posterior, anterior, dorsal, and side views of the holotype, ×1, USNM 148522a; 26–28, dorsal, side, and anterior views, ×2, of the holotype; 29, 30, interior of the pedicle valve, ×1, ×2, tilted to show the dental plates, paratype USNM 154653g; 31, interior of the brachial valve, ×2, paratype USNM 154653b. [Road Canyon Formation, USNM 703a.]

Deltarina magnicostata, new species: 32, 33, Dorsal, posterior, side, anterior, and ventral views, ×1, of two immature paratypes USNM 154651a, b; 34, dorsal, posterior, side, anterior, and ventral views, ×1, of an adult individual, paratype USNM 152815d; 35–37, anterior, side, and dorsal views of the preceding specimen, ×′2; 38, dorsal, posterior, side, anterior, and ventral views of a young adult, ×1, paratype USNM 154651b; 39, dorsal, posterior, side, anterior, and ventral views, ×1, of the holotype USNM 154651c; 40–42, side, anterior, and dorsal views, ×2, of the holotype; 43, 44, brachial valve tilted and in interior view, ×3, showing cardinalia, paratype USNM 154651f; 46, 47, interior of the pedicle valve, ×3, ×1.5, showing interarea, paratype USNM 154651d; 48, side view of a specimen from which the pedicle beak has been broken to show the crura, ×3, paratype USNM 154651e. [Bell Canyon Formation (Lamar Member), USNM 725e.]

45, Interior of a brachial valve, ×3, showing cardinalia, paratype USNM 154656h; 49, 50, interior of two pedicle valves, ×1.5, paratypes USNM 154656a, b; 51, 56, interior of the pedicle valve, ×1.5, ×3, showing teeth and main palliai trunks, paratype USNM 154656c; 52, interior of another pedicle valve, ×1.5, paratype USNM 154656d; 53, anterior view, ×3, showing cardinalia and dental plates, paratype USNM 154656e; 54, posterior of the brachial valve. ×6, showing the cardinalia, paratype USNM 154656i; 55, posterior of another brachial valve, ×6, showing the cardinalia, paratype USNM 154656g. [Bell Canyon Formation (Lamar Member), USNM 738.]

Tricoria hirpex, new species: 57–61, Anterior, posterior, ventral, side, and dorsal views, ×1, holotype USNM 154652; 62, 63, interior of the pedicle valve of the holotype, ×2, showing musclc scars; 64, 65, interior of the brachial valve of the holotype, ×2, showing cardinalia; 66, 67, the two preceding views enlarged, ×4, showing cardinalia and crura in detail; 68, interior of a pedicle valve, ×4, showing pallial marks, paratype USNM 148155m; 69–71, anterior, side, and dorsal views of a complete specimen, ×2, paratype USNM 148155j (for natural size views, see Plate 503: figure 31). [Skinner Ranch Formation (base), USNM 705a.]

PLATE 507.—Chaeniorhynchus, Deltarina, and Tricoria

PLATE 508

Pontisia, Strigirhynchia, Deltarina, Phrenophoria, Bryorhynchus, Chaeniorhynchus, Lirellaria, Cenorhynchia, and Ptilotorhynchus

Pontisia robusta, new species: 1–5, Ventral, posterior, side, anterior, and dorsal views of a complete specimen, ×1, holotype USNM 154664a. [Cibolo Formation (Breccia Zone of Udden), USNM 728–1.]

Strigirhynchia indentata (Shumard): 6–10, Dorsal, anterior, ventral, side, and posterior views, ×1, of a young specimen, hypotype USNM 148530a; 11, 12, dorsal and side views of the preceding specimen, ×2, [Capitan Formation, USNM 737a.]

13–17, Dorsal, anterior, side, posterior, and ventral views of a small, complete specimen, ×1, hypotype USNM 154659a; 18–20, anterior, dorsal, and side views, ×2, of the preceding specimen. [Capitan Formation USGS 7404.]

21–23, Dorsal, anterior and side views, ×2, of a complete specimen, hypotype USNM 154661a. [Capitan Formation, USNM 725–1.]

24–28, Posterior, ventral, side, dorsal, and anterior views of a silicified specimen, ×1, hypotype USNM 154660. [Bell Canyon Formation (Lamar Member), USNM 728p.]

29, Interior of a brachial valve, ×3, showing an undivided hinge plate, hypotype USNM 148531. [Bell Canyon Formation (Lamar Member), USNM 728p.]

Deltarina magnicostata, new species: 30–33, Anterior, side, and dorsal views, ×1, and dorsal view, ×2, paratype USNM 154658. [Bell Canyon Formation (Lamar Member) USNM 728p.]

Phrenophoria perplexa, new species: 34–39, Dorsal, posterior, side, ventral, and anterior views, ×1, and dorsal view, ×1.5, paratype USNM 154665a. [Bell Canyon Formation (Rader Member), USNM 740a.]

Bryorhynchus bisulcatum (Shumard): 40–43, Posterior, ventral, dorsal, and anterior views of an anteriorly costate individual, ×1, hypotype USNM 154931a; 44–47, ventral, anterior, dorsal, and posterior views of another hypotype with strong costae, ×1, USNM 154931b. [Bell Canyon Formation (Rader Member), USNM 740j.]

Chaeniorhynchus transversum, new species: 48–55, Anterior, dorsal, posterior, side, and ventral views, ×1, and dorsal, side, and anterior views, ×2, holotype USNM 148523. [Cathedral Mountain Formation, USNM 703b.]

Lirellaria costellata, new species: 56, Posterior, anterior, side, ventral, and dorsal views of a complete specimen, ×1, paratype USNM 154667: 57–60, dorsal view, ×1, and anterior, dorsal, and side views, ×2, holotype USNM 155073a; 61–64, dorsal view, ×1, and anterior, side, and dorsal views, ×2, paratype USNM 155073b. [Bell Canyon Formation (Lamar Member), USNM 728p.]

Cenorhynchia saginata, new species: 65–67, Anterior, side and dorsal views of a complete specimen, ×2, paratype USNM 154666a. [Cibolo Formation (thin-bedded zone], USNM 738–1.]

Phrenophoria species 3: 68–70, Exterior, interior, and interior laterally tilted views of the brachial valve, ×1, figured specimen USNM 154663; 71, interior of the preceding specimen, ×4, showing undivided hinge plate. [Road Canyon Formation, USNM 721j.]

Ptilotorhynchus delicatum, new species: 72, 73, Posterior and dorsal views of a young specimen with a reflected lip on the deltidium, ×4, paratype USNM 154668a; 74, 75, posterior, and dorsal views of another young specimen with labiate foramen, ×4, paratype USNM 154668b. [Bell Canyon Formation (Lamar Member), USNM 728p.]

76, Dorsal view of another, elongate, young specimen having a labiate foramen, ×6, paratype USNM 154670. [Bell Canyon Formation (Lamar Member), USNM 738b.]

PLATE 508.—Pontisia, Strigirhynchia, Deltarina, Phrenophoria, Bryorhynchus, Chaeniorhynchus, Lirellaria, Cenorhynchia, and Ptilotorhynchus.

PLATE 509

Divaricosta, Fascicosta, and Allorhynchus

Divaricosta squarrosa Cooper and Grant: 1–5, Anterior, posterior, ventral, side, and dorsal views, ×1, lectotype AMNH 27904/1; 6–8, dorsal, side, and anterior views of the preceding lectotype, ×2, 9, dorsal, posterior, side, anterior, and ventral views, ×1, of another complete specimen, paratype AMNH 27904/2; 10, 11, interior of the pedicle valve, ×1.5, and posterior of same specimen, ×3, paratype AMNH 27904/4; 12–15, exterior, interior, and interior tilted views, and posterior, ×3, of a pedicle valve, showing the deltidium, teeth, and dental plates, hypotype USNM 154675a; 16, interior of another pedicle valve, ×2, hypotype USNM 154675b; 17, interior of a brachial valve, ×1.5, showing hinge plate, paratype AMNH 27904/6; 18–20, laterally tilted and interior views of the brachial valve, ×4, and cardinalia with undivided hinge plate, ×6, of another brachial valve, hypotype USNM 154675c; 21, 22, interior of the pedicle and brachial valves of a small individual, ×1, hypotype USNM 148221; 23, interior of the pedicle valve of the preceding specimen enlarged, ×3; 24–26, interior, posteriorly tilted, and laterally tilted views of the preceding brachial valve, ×3, showing divided hinge plate and long crura. [Cherry Canyon Formation (Getaway Member), AMNH 512 = USNM 728.]

Fascicosta longaeva (Girty): 27–32, Posterior, anterior, side, ventral, and dorsal views, ×1, and dorsal view, ×2, of the lectotype USNM 118573a. [Capitan Formation, USGS 2926 (green).]

33–40, Anterior, posterior, side, ventral, and dorsal views, ×1, and anterior, side, and dorsal views, ×2, of a complete specimen, hypotype USNM 152816a; 41–48, anterior, dorsal, ventral, side, and posterior views, ×1, and dorsal, side, and anterior views, ×2, of another complete specimen, hypotype USNM 152816b. [Capitan Formation, USNM 750b.]

49–53, Posterior, side, dorsal, ventral, and anterior views, ×1, of a complete specimen, hypotype USNM 148247a. [Capitan Formation, USNM 737a.]

54, 55, Interior of the brachial valve, ×3, showing a divided hinge plate and tilted to show the median septum, hypotype USNM 148246. [Bell Canyon Formation (Pinery Member), USNM 736.]

56–59, Specimen with brachial valve broken away and showing the under side of the crura, ×1, and the same view, ×2, hypotype USNM 154677. [Bell Canyon Formation (Lamar Member), USNM 738.]

Divaricosta vagabunda, new species: 60, 61, Dorsal and ventral views, ×1, and dorsal view, ×2, holotype USNM 154674. [Word Formation (Appel Ranch Member), USNM 719z.]

Fascicosta elongata, new species: 62, Dorsal, posterior, side, anterior, and ventral views, ×1, of a complete specimen, holotype USNM 152817; 63–67, dorsal, ventral, posterior, anterior, and side views of the preceding specimen, ×2, [Bell Canyon Formation (Pinery Member), AMNH 33.]

Fascicosta bella, new species: 68, Dorsal, posterior, side, anterior, and ventral views, ×1, of a complete specimen, paratype USNM 154679: 69–73, Anterior, side, ventral, posterior, and dorsal views, ×2, of the same paratype. [Bell Canyon Formation (Rader Member), AMNH 410.]

Allorhynchus concentricum, new species: 74–77, Anterior, dorsal, side views, ×1, and dorsal view, ×2, figured specimen USNM 154676. [Road Canyon Formation, USNM 732.]

PLATE 509.—Divaricosta, Fascicosta, and Allorhynchus.

PLATE 510

Strigirhynchia, Paranorella, Cenorhynchia, Bryorhyjichus, Anteridocus, Cleiothyridina, and Pontisia

Strigirhynchia elongata, new species: 1, Posterior, anterior, side, ventral, and dorsal views, ×1, paratype USNM 154687 (broken); 2–4, side, anterior, and dorsal views of the preceding specimen, ×2; 5–11, dorsal view, ×1, and ventral, dorsal, side, anterior, and posterior views, ×2, and dorsal view, ×4, showing the deltidial plates with reflected lip, holotype USNM 154688a; 12, interior of the brachial valve, ×3, showing hinge plate and median septum, paratype USNM 154688b. [Bell Canyon Formation (Lamar Member), USNM 728p.]

38, Dorsal, ×2, and dorsal, side, and anterior views, ×1, of a small specimen, paratype USNM 155133. [Bell Canyon Formation (Lamar Member), USNM 728i.]

Paranorella species 2: 13–15, Ventral and dorsal views, ×1, and dorsal view, ×2, of an immature individual, figured specimen USNM 154690a; 16, 17, exterior and interior views, ×1, of the pedicle valve, figured specimen USNM 154690b; 18, 19, exterior and interior of a brachial valve, ×1, figured specimen USNM 154690c; 20, interior of the preceding brachial valve, ×2, showing the cardinalia. [Bone Spring Formation, USNM 728e.]

Paranorella species 6: 21–23, Interior and exterior, ×1, and interior, ×2, of a pedicle valve, figured specimen USNM 154689a; 24–26, interior and exterior, ×1, and interior, ×2, of a brachial valve, showing the cardinalia, figured specimen, USNM 154689b. [Skinner Ranch Formation (Dugout Mountain Member), USNM 732e.]

Cenorhynchia camerata, new species: 27–29, Dorsal, side, and anterior views, ×2, paratype USNM 155069a (for natural size, see Plate 521: figures 53–57); 30, interior, ×3, showing crura and septum, paratype USNM 155069g; 31, 32, interior of two dorsal valves, ×3, showing hinge plate and septum, paratypes USNM 155069h, i. [Neal Ranch Formation (bed 4), USNM 727e.]

Cenorhynchia saginata, new species: 33, Anterior, posterior, side, dorsal, and ventral views of a complete adult, ×1, paratype USNM 153487; 34–37, side, anterior, ventral, and dorsal views of the same specimen, ×2, [Neal Ranch Formation (bed 4), USNM 727e.]

Bryorhynchus nitidum (Girty): 39–43, Anterior, dorsal, side, posterior, and ventral views, ×1, of the holotype USNM 118563. [Bone Spring Formation, USGS 2920 (green).]

Anteridocus bicostatus, new species: 44–47, Posterior, anterior, side, ventral, and dorsal views, ×1, and anterior, dorsal and side views, ×2, of a complete specimen, paratype USNM 154685.[Bell Canyon Formation (Hegler Member), USNM 731.]

Cleiothyridina rara, new species: 48–55, Dorsal, posterior, anterior, ventral, and side views, ×1, and anterior, dorsal, and side views, ×2, of a complete specimen, holotype USNM 154518. [Word Formation (Willis Ranch Member), USNM 706e.]

Pontisia stehlii tumidosa, new subspecies: 56, Posterior, anterior, side, ventral, and dorsal views, ×1, paratype USNM 154686a; 57–59, anterior, side, and dorsal views, ×2, of same specimen; 60, 61, Anterior view, ×1, ×4, showing the cardinalia, paratype USNM 154686b; 62, interior of the pedicle valve, ×2, showing disjunct deltidial plates, paratype USNM 154686c. [Cathedral Mountain Formation, USNM 726u.]

PLATE 510.—Strigirhynchia, Paranorella, Cenorhynchia, Bryorhynchus, Anteridocus, Cleiothyridina, and Pontisia.

PLATE 511

Lirellaria and Aphaurosia

Lirellaria costellata, new species: 1–4, Ventral, posterior, side, anterior, and dorsal views, ×1, and dorsal, anterior, and side views, ×2, of the paratype USNM 152819. [Bell Canyon Formation (Lamar Member), AMNH 40.]

5, 6, Interior and posteriorly tilted views of the brachial valve, ×3, showing cardinalia and slight median ridge, paratype USNM 154696a. [Bell Canyon Formation (Lamar Member), USNM 725e.]

7–9, Exterior, ×1, and exterior and interior, ×2, of the pedicle valve, paratype USNM 154692a; 10, posterior of the preceding pedicle valve, ×4, showing small, disjunct deltidial plates; 11, 12, dorsal view of the interior of a brachial valve, ×1, ×3, showing the crura, paratype USNM 154692b. [Bell Canyon Formation (Lamar Member), USNM 738.]

13, Dorsal, posterior, side, anterior, and ventral views, ×1, of a young specimen, paratype USNM 152821a; 14–17, dorsal, posterior, side, anterior, and ventral views, ×1, and side, anterior and dorsal views, ×2, of a complete individual, paratype USNM 152821c. [Bell Canyon Formation (Lamar Member), AMNH 40.]

18, 19, Interior of the pedicle valve, ×1, ×4, showing conjunct deltidial plates, paratype USNM 154693b; 20, interior of the brachial valve, ×4, paratype USNM 154693a. [Bell Canyon Formation (Lamar Member), USNM 725e.]

Lirellaria? species 1: 21. Exterior, interior tilted to show dental plates, and interior views of a pedicle valve, ×1, figured specimen USNM 152823; 22, beak of the preceding, ×2, [Word Formation (Willis Ranch Member), USNM 706e.]

Lirellaria diabloensis, new species: 23, 24, Dorsal, side, posterior, and ventral views of a damaged specimen, ×1, dorsal view, ×2, holotype USNM 152822; 25, posterior of the preceding specimen, ×4, showing conjunct deltidial plates. [Bone Spring Formation, AMNH 591.]

Aphaurosia rotundata, new species: 26–30, Ventral, anterior, side, and dorsal views, ×1, and dorsal view, ×2, of a complete specimen, paratype USNM 152808. [Bell Canyon Formation (Rader? Member), AMNH 404.]

31–38, Anterior, posterior, side, ventral, and dorsal views, ×1, and dorsal, side, and anterior views, ×2, of the paratype USNM 152806b; 39–43, posterior, anterior, dorsal, side, and ventral views, ×1, of another complete specimen, paratype USNM 152806a; 49–51, interior of the brachial valve, ×1.5, and tilted and interior views, ×3, showing the hinge plate and crura, paratype USNM 154694b. [Bell Canyon Formation (Lamar Member), USNM 738.]

44–48, Anterior, side, posterior, ventral, and dorsal views, ×1, of a damaged specimen, paratype USNM 152807b; 52–54, interior, ×1.5, and interior and posteriorly tilted views, ×3, showing the cardinalia, paratype USNM 154695a; 55–58, laterally tilted to right, ×1, and laterally tilted to right and left views, and interior view, ×4, of another brachial valve showing hinge plate and crura, paratype USNM 154695c; 59, interior, ×3, of an incomplete specimen showing dorsal side of crura and hinge plate, paratype USNM 154695b; 60, posterior of a brachial valve, ×4, showing the hinge plate, paratype USNM 154695c; 61–64, posterior, anterior, side, dorsal, and ventral views, ×1, and anterior, side, and dorsal views, ×2, of a complete specimen, paratype USNM 154927. [Bell Canyon Formation (Lamar Member), USNM 725e.]

PLATE 511.—Lirellaria and Aphaurosia.

PLATE 512

Amphipella and Acolosia

Amphipella arcaria Cooper and Grant: 1–4, Ventral, posterior, side, anterior, and dorsal views, ×2, ×1, of four paratypes USNM 148098a’, d’, f’, g′; 5–10, ventral, posterior, side, anterior, and dorsal views, ×2, dorsal view, ×1, and side, posterior, anterior, dorsal, and ventral views, ×6, holotype USNM 148098a; 11–16, ventral, posterior, side, anterior, and dorsal views, ×2, dorsal view, ×1, and side, posterior, anterior, ventral, and dorsal views, ×6, hypotype USNM 154702f; 17–21, posterior, anterior, side, dorsal, and ventral views of another complete specimen, ×6, hypotype USNM 154702a; 22–24, posterior, side, and dorsal views of a complete specimen, ×4, hypotype USNM 154700a; 25, dorsal view of a specimen distorted in life, ×4, hypotype USNM 154700b; 26, anterior view of the interior, ×6, showing shelly pouches and cardinalia, paratype USNM 148098b; 27, interior of the pedicle valve, ×4, showing pouches and dental lamellae, hypotype USNM 154700c; 28, 29, interior tilted posteriorly and in full view of another pedicle valve, ×4, showing pouches and dental plates, hypotype USNM 154700d; 30, another pedicle valve tilted to show the dental plates, ×4, hypotype USNM 154700f; 31, interior of another pedicle valve, ×4, showing the teeth, hypotype USNM 154700e; 32, side view of a specimen partially broken to show closed pouch, ×6, hypotype USNM 154700g; 33, specimen with part of the pedicle valve removed to show pouches and cardinalia, ×6, hypotype USNM 154702h; 34, interior showing the long crura, ×4, paratype USNM 154700h; 35, interior of a brachial valve, ×6, showing undivided hinge plate and long crura, hypotype USNM 154702i; 36, partial side view of a specimen broken to show the pouch and cardinalia, ×4, paratype USNM 148098c; 37, interior of a distorted brachial valve, ×4, hypotype USNM 154700i; 38, 39, posteriorly tilted and interior views of a brachial valve, ×4, showing nearly complete hinge plate, hypotype USNM 154700j; 40, interior of the pedicle valve, ×6, hypotype USNM 154700k; 41, 42, interior of two brachial valves, ×6, showing cardinalia, hypotype USNM 154700o and paratype 149098d; 43, 44, interior and laterally tilted views of another brachial valve with incomplete hinge plate, ×4, hypotype USNM 154700–l; 45, 46, posteriorly tilted and interior views of a brachial valve, ×4, hypotype USNM 154702d; 47, interior of the pedicle valve with cardinalia of brachial valve seen in dorsal view, ×4, hypotype USNM 154700n. [Cathedral Mountain Formation (base), USNM 708u.]

Amphipella attenuata, new species: 48, 49, Interior of a pedicle valve, ×3, ×9, holotype USNM 148102. [Road Canyon Formation, USNM 703a.]

Acolosia? anomala, new species: 50–53, Dorsal, anterior, side, posterior, and ventral views, ×1, and anterior, side, and dorsal views, ×2, of the holotype USNM 152799a; 54, ventral side of the holotype, ×2, showing cardinalia; 55, 56, posterior of the holotype tilted and in normal view to show the cardinalia, ×6, [Word Formation (Willis Ranch Member), USNM 706e.]

PLATE 512.—Amphipella and Acolosia.

PLATE 513

Ptilotorhynchus, Iotina, Acolosia, and Madarosia

Ptilotorhynchus delicatum, new species; 1–5, Anterior, posterior, dorsal, side, and ventral views, ×1, of the holotype USNM 148219. [Capitan Formation, USNM 739.]

6, 7, Dorsal view of a crushed specimen, ×1, ×2, paratype USNM 154711. [Bell Canyon Formation (Lamar Member), AMNH 430.]

8, Ventral, posterior, side, anterior, and dorsal views, ×3, of a young specimen, paratype USNM 154713. [Cherry Canyon Formation (Getaway Member), USNM 732.]

9–12, Interior, ×2, ×6, and interior laterally tilted, ×2, ×6, of a brachial valve showing the cardinalia, paratype USNM 154710a; 13, interior of the pedicle valve belonging to the preceding, ×6, sohwing conjunct deltidial plates and reflected foramenal edge, paratype USNM 154710a; 16, 17, interior of pedicle valve, ×2, ×8, showing deltidial plates with their reflected margin, paratype USNM 154710e; 18, posterior of another pedicle valve, ×4, showing deltidium and foramen, paratype USNM 154710h. [Bell Canyon Formation (Lamar Member), USNM 725e.]

14, 15, Interior of the brachial valve, ×2, ×6, showing the cardinalia, paratype USNM 154714. [Bell Canyon Formation (Lamar Member), USNM 738.]

Iotina minuta, new species: 19, Ventral, posterior, side, anterior, and dorsal views, ×2, and dorsal view, ×1, paratype USNM 152818a; 20–23, ventral, posterior, side, anterior, and dorsal views, ×2, dorsal view, ×1, and dorsal, anterior, and side views, ×4, holotype USNM 152818b; 24–26, interior of the brachial valve, ×2, and interior and laterally tilted views, ×4, paratype USNM 152818i; 27–29, interior of the pedicle valve, ×2, and posteriorly tilted and interior views of the same specimen, ×4, paratype USNM 152818j. [Bone Spring Formation, AMNH 591.]

Acolosia elliptica, new species: 30–35, Anterior, side, posterior, ventral, dorsal, ×1, and dorsal views, ×2, holotype USNM 148203a; 36–38, anteriorly tilted, interior, and laterally tilted views of the brachial valve, ×6, paratype USNM 148203b. [Hess Formation (Taylor Ranch Member), USNM 702d.]

Madarosia pentagona, new species: 39, Interior of the pedicle valve, ×2, showing dental plates, paratype USNM 154930; 40, 41, laterally tilted and interior views of the brachial valve of the same specimen, ×2, showing cardinalia (for exterior views see Plate 548: figure 18). [Cherry Canyon Formation (Getaway Member), AMNH 512.]

Acolosia glabra, new species: 42, Ventral, posterior, side, anterior, and dorsal views of a complete specimen, ×1, paratype USNM 148173b; 43, ventral, posterior, side, anterior, and dorsal views, ×1, of another complete specimen, paratype USNM 148173a; 44–47, ventral, posterior, side, anterior and dorsal views, ×1, and dorsal, anterior, and side views, ×2, holotype USNM 148173e; 48, 49, ventral views of a specimen with pedicle valve partially removed to show cardinalia, ×2, ×6, paratype USNM 148173d; 50, 51, interior of the pedicle valve, and posteriorly tilted views, ×2, showing lack of deltidial plates and presence of dental plates, paratype USNM 154715c; 52, interior of brachial valve, ×2, showing an undivided hinge plate, paratype USNM 154715e; 53, 54, interior and laterally tilted views of a brachial valve, ×2, showing divided hinge plate, paratype USNM 154715d; 55, 56, interior and laterally tilted views of the preceding specimen, ×6, showing the hinge plate. [Word Formation (China Tank Member). USNM 706c.]

Acolosia recepta, new species: 57–60, Anterior, dorsal, ×1, posterior, ventral, side, and dorsal views, ×2, and posterior, anterior, and side views, ×4, holotype USNM 152801a; 61, 62, posteriorly tilted and interior views of the pedicle valve, ×6, paratype USNM 152801b; 63, 64, laterally tilted and interior views of the brachial valve, ×6, showing cardinalia, paratype USNM 152801c. [Skinner Ranch Formation (Poplar Tank Member), USNM 707h.]

PLATE 513.—Ptilotorhynchus, lotina, Acolosia, and Madarosia.

PLATE 514

Strigirhynchia and Phrenophoria

Strigirhynchia transversa, new species: 1–5, Posterior, anterior, side, ventral, and dorsal views of a large adult, ×1, holotype USNM 152863a; 6–11, posterior, anterior, side, ventral, and dorsal views, ×1, and dorsal view, ×1.5, paratype USNM 152863b; 12–17, posterior, anterior, side, dorsal, and ventral views, ×1, and dorsal view, ×1.5, of a young adult, paratype USNM 152863c. [Captain Formation, USNM 750a.]

18–23, Anterior, side, posterior, dorsal, and ventral views, ×1, and dorsal view, ×1.5, paratype USNM 154716. [Capitan Formation, USNM 725k.]

24–28, Anterior, posterior, ventral, side, and dorsal views, ×1, paratype USNM 154717. [Capitan Formation, USNM 740.]

Phrenophoria bicostata, new species: 29, 30, Ventral, posterior, side, anterior and dorsal views, ×1, and dorsal view, ×2, of a complete specimen, paratype USNM 152825m; 31–34, ventral, posterior, side, anterior, and dorsal views, ×1, and dorsal, anterior, and side views, ×3, paratype USNM 152825n; 35, 36, interior of pedicle valve, ×2, ×6, showing teeth and disjunct deltidial plates, paratype USNM 152825k; 37, 38, interior and laterally tilted views of the brachial valve, ×2, paratype USNM 152825i; 39, interior of the preceding brachial valve, ×6, showing the undivided hinge plate. [Word Formation (Appel Ranch Member), USNM 719z.]

Phrenophoria corpulenta, new species: 40–44, Posterior, anterior, side, ventral, and dorsal views, ×1, holotype USNM 152826f; 45–49, ventral, posterior, side, anterior, and dorsal views of a young specimen, ×1, paratype USNM 152826d: 50, dorsal view, ×2, of an adult, paratype USNM 152826h; 51, 52, dorsal, anterior, side, and dorsal views, ×1, of two young and compressed individuals, paratypes USNM 152826a, b; 53, interior, posteriorly tilted, and laterally tilted views, ×2, paratype USNM 154718; 54, posterior part of the preceding specimen, ×6, showing the undivided hinge plate and median septum. [Bone Spring Formation (Cutoff Member), AMNH 678.]

Phrenophoria depressa, new species: 55–58, Ventral, posterior, side, anterior, and dorsal views, ×1, and anterior, side, and dorsal views, ×2, of a complete specimen, paratype USNM 148773b; 59–62, ventral, posterior, side, anterior, and dorsal views, ×1, and anterior, dorsal, and side views, ×2, holotype USNM 148773a; 63–65, interior posteriorly tilted, interior, and laterally tilted views of the brachial valve, ×1.5, paratype USNM 148773i; 66–68, interior, posteriorly tilted, and laterally tilted views of the preceding specimen, ×2, showing the undivided hinge plate; 69, interior of the same brachial valve, ×3, tilted to show median septum and muscle scars; 70, 71, interior and posteriorly tilted views of the pedicle valve, ×2, showing the dental plates, paratype USNM 148773h. [Skinner Ranch Formation (Sullivan Peak Member), USNM 707d.]

PLATE 514.—Strigirhynchia and Phrenophoria.

PLATE 515

Cenorhynchia, Anteridocus, Acolosia?, Aphaurosia, Wellerella, Tautosia, Phrenophoria, and Pontisia

Cenorhynchia fracida, new species: 1–4, Posterior, anterior, side, ventral, and dorsal views, ×1, and anterior, side, and dorsal views, ×3, paratype USNM 154721. [Word Formation (Willis Ranch Member), USNM 706e.]

36–41, Dorsal view, ×1, and side, anterior, posterior, ventral, and dorsal views, ×2, of a damaged specimen, paratype USNM 154722; 42, dorsal view, ×4, of the preceding specimen. [Word Formation (Appel Ranch Member), USNM 727j.]

Anteridocus paucicostatus, new species: 5, 7, Ventral, posterior, side, anterior, and dorsal views, ×2, and dorsal view, ×1, of two paratypes USNM 154723a, c; 6, ventral, posterior, side, anterior, and dorsal views, ×2, and dorsal view, ×1, holotype USNM 154723b. [Skinner Ranch Formation (Sullivan Peak Member), USNM 733j.]

Acolosia? exasperata, new species: 8–11, Posterior, anterior, side, dorsal, and ventral views, ×1, and dorsal, anterior, and side views, ×2, holotype USNM 152800a. [Skinner Ranch Formation (base), USNM 720e.]

Aphaurosia scutata, new species: 12, Ventral, posterior, side, anterior, and dorsal views, ×1, paratype USNM 154727. [Bell Canyon Formation (Lamar Member), USNM 738.]

13–16, Ventral, posterior, side, anterior, and dorsal views, ×1, and dorsal, anterior, and side views, ×2, holotype USNM 154726. [Bell Canyon Formation (Lamar Member), USNM 725e.]

17–21, Anterior, posterior, side, ventral, and dorsal views of a complete specimen, ×1, paratype USNM 154725b; 22, interior of the pedicle valve, ×1, showing the dental plates, paratype USNM 154724a; 23, interior of the brachial valve, ×1, paratype USNM 154724b; 24, 25, interior tilted and in direct view of the preceding specimen, ×3, showing the hinge plate and crura. [Bell Canyon Formation (Lamar Member), USNM 738b.]

Wellerella girtyi girtyi, new subspecies: 26–28, Interior, posteriorly tilted, and laterally tilted views of the brachial interior, ×4, showing the hinge plate and crura, paratype USNM 154733b. [Word Formation (Willis Ranch Member), USNM 706e.]

Tautosia cf. T. pulchra, new species: 29, Interior of a brachial valve, ×3, showing cardinalia and median septum, paratype USNM 154730. [Cathedral Mountain Formation, USNM 721u.]

Phrenophoria bicostata, new species: 30, Dorsal view, ×1, and posterior, anterior, side, ventral, and dorsal views, ×2, holotype USNM 154729a; 31, 32, exterior and interior, ×2, of the brachial valve, paratype USNM 154729b; 33, 34, exterior and interior of another brachial valve, ×2, paratype USNM 154729c; 35, interior of the preceding specimen, ×4, showing the hinge plate and median septum. [Word Formation (Appel Ranch Member), USNM 719z.]

Pontisia nanas (Stehli): 43, Dorsal view, ×1, and posterior, anterior, side, dorsal, and ventral views, ×2, hypotype USNM 154728a; 44, broken specimen, ×2, showing dorsal side of cardinalia and absence of a median septum, hypotype USNM 154728b. [Bone Spring Formation, USNM 725c.]

Cenorhynchia saginata, new species: 45–48, Ventral, posterior, side, anterior, and dorsal views, ×1, and dorsal, side, and anterior views, ×2, of a complete specimen, paratype USNM 154731a; 49–52, ventral, posterior, side, anterior, and dorsal views, ×1, and dorsal, side, and anterior views, ×2, of another paratype USNM 154731b; 53–56, ventral, posterior, side, anterior, and dorsal views, ×1, and anterior, side, and dorsal views, ×2, paratype USNM 154731c. [Cibolo Formation (Thin-bedded Zone of Udden), USNM 738–1.]

PLATE 515.—Cenorhynchia, Anteridocus, Acolosia?, Aphaurosia, Wellerella, Tautosia, Phrenophoria, and Pontisia.

PLATE 516

Pontisia and Phrenophoria

Pontisia truncata, new species: 1–3, Side, dorsal, and anterior views, ×1, of the holotype, USNM 154734; 4, 5, interior of the brachial and pedicle valves of the holotype, ×2, showing conjunct deltidial plates and undivided hinge plate. [Road Canyon Formation, USNM 732j.]

Phrenophoria nesiotes, new species: 6–10, Posterior, anterior, side, dorsal, and ventral views, ×1, of a paratype USNM 148355f; 11–15, posterior, anterior, side, ventral, and dorsal views, ×1, holotype USNM 148355h; 16–20, ventral, dorsal, posterior, side, and anterior views of another complete specimen, ×1, paratype USNM 148355j; 21–25, posterior, side, anterior, ventral, and dorsal views of an adult, ×1, paratype USNM 148355g; 26–30, anterior, posterior, side, ventral, and dorsal views of a young adult, ×1, paratype USNM 148355i; 31, dorsal views, ×1, immature paratypes 148355a, a’ (top row), 148355b (middle row), and 148355c (bottom row); 32, ventral view of a specimen broken to show the cardinalia, ×1.5, paratype USNM 148673c; 33, 34, two paratypes in partial side view, ×1.5, showing cardinalia and median septum, USNM 148673b, a; 35, ventral view of another broken specimen, ×1, showing the cardinalia, paratype USNM 148673d; 36, interior of the pedicle valve, ×1, showing disjunct deltidial plates, paratypes USNM 154735c; 37, posterior of a fragmentary brachial valve, ×6, showing the undivided hinge plate and median septum, paratype USNM 154735b; 38, hinge plate of another brachial valve, ×6, paratype USNM 154735a; 39, 40, fragmentary brachial valve, ×2, ×6, showing hinge plate and median septum, paratype USNM 154735e; 41, 42, posterior and side views of another fragmentary brachial valve, ×6, showing the crura, paratype USNM 154735d. [Cathedral Mountain Formation, USNM 708u.]

Phrenophoria perplexa, new species: 43–48, anterior, posterior, side, ventral, and dorsal views, ×1, and posterior, ×3, showing conjunct deltidial plates, paratype USNM 152828a; 58, ventral view of the interior, ×2, showing dental plates and cardinalia, paratype USNM 154736–l. [Bell Canyon Formation (Rader Member), USNM 725f.]

49–53, posterior, side, anterior, ventral, and dorsal views, ×1, holotype USNM 154595a; 54, posterior of the pedicle valve, ×3, showing the conjunct deltidial plates, paratype USNM 154595b, [Bell Canyon Formation (Rader Member), USNM 740j.]

55, 57, interior of two specimens, ×3, showing the hinge plate, crura and median septum, paratypes USNM 155074f, c. [Bell Canyon Formation (Rader Member), USNM 740a.]

56, interior of the posterior of both valves, ×3, showing median septum and dental plates, paratype USNM 155075–l. [Bell Canyon Formation (Rader Member), USNM 740j.]

PLATE 516.—Pontisia and Phrenophoria.

PLATE 517

Antronaria, Anteridocus, Pontisia, Cenorhynchia, Phrenophoria, and Madarosia

Antronaria mesicostalis (Girty): 1–5, Anterior, posterior, side, ventral, and dorsal views, ×1, paratype USNM 154742a; 6–10, ventral, dorsal, side, posterior, and anterior views, ×1, paratype USNM 154742b; 11–15, posterior, anterior, side, ventral, and dorsal views of a young individual, ×1, paratype USNM 154742c; 16, 17, posteriorly tilted and interior views of the brachial valve, ×2, showing the hinge plate and lack of median septum, paratype USNM 154742d. [Bone Spring Formation, USNM 728e.]

Anteridocus seminudus, new species: 18, Ventral, posterior, side, anterior, and dorsal views, ×2, and dorsal view, ×1, paratype USNM 154746a; 19, 20, ventral, posterior, side, anterior, and dorsal views, ×2, and dorsal view, ×1, of two paratypes USNM 154746b, c. [Road Canyon Formation, USNM 724b.]

Pontisia stehlii stehlii Cooper and Grant: 21–24, Posterior, anterior, side, ventral, and dorsal views, ×1, and anterior, side, and dorsal views, ×2, paratype USNM 154743a; 25, interior of the brachial valve, ×3, showing the hinge plate and lack of median septum, paratype USNM 154743b. [Cathedral Mountain Formation, USNM 726o.]

38–42, Ventral, posterior, side, anterior, and dorsal views, ×1, of five paratypes USNM 154745a–d, f; 43, ventral, posterior, side, anterior, and dorsal views, ×1, paratype USNM 154745g; 44, dorsal view of an immature specimen, ×1, paratype USNM 154745e; 45, ventral view of a specimen with ventral beak region removed to show the cardinalia, ×2, paratype USNM 1547451h; 46, interior of the brachial valve, ×1, paratype USNM 154745j; interior ot the brachial valve, ×3, showing the cardinalia, paratype USNM 154745i. [Cathedral Mountain Formation, USNM 726o.]

Madarosia anterolamellata, new species: 48–52, Dorsal, posterior, side, ventral, and anterior views of a complete specimen, ×1, holotype USNM 154744a; 53, anterior of a paratype, ×1, showing the anterior lamellae, USNM 154744b; 54, broken specimen, ×2, showing delicate cardinalia and median septum, paratype USNM 154744c. [Bell Canyon Formation (Rader Member), USNM 725f.]

Cenorhynchia species 1: 26–30, Anterior, posterior, side, dorsal, and ventral views, ×2, figured specimen USNM 153492a; 31–35, dorsal, ventral, side, posterior, and anterior views, ×2, of a complete individual, figured specimen USNM 153492b. [Skinner Ranch Formation, USNM 726h.]

Phrenophoria pentagonalis, new species: 36, 37, Ventral, posterior, side, anterior, and dorsal views, ×1, of the holotype and a paratype USNM 148575a, b. [Road Canyon Formation, USNM 703d.]

PLATE 517.—Antronaria, Anteridocus, Pontisia, Cenorhynchia, Phrenophoria, and Madarosia.

PLATE 518

Phrenophoria

Phrenophoria pinguiformis new species: 1–5, Dorsal, posterior, side, anterior, and ventral views, ×1, of the holotype USNM 148394c; 6–8, interior, posteriorly tilted, and laterally tilted views of the brachial valve of the holotype, ×1, showing cardinalia and median septum; 9, 10, interior and posteriorly tilted views of the pedicle valve of the holotype, ×1, showing dental plates and disjunct deltidial plates; 22, interior of the preceding specimen, ×1.5, showing muscle scars; 11–15, dorsal, side, anterior, and ventral views, ×1, showing cardinalia, and ventral view, ×2, showing the crura, paratype USNM 148394d; 16, interior of the brachial valve, ×1, paratype USNM 148394p; 17, 18, posteriorly and laterally tilted views, ×1.5, showing hinge plate of the preceding specimen; 19, posterior of the preceding specimen, ×3, showing the hinge plates not quite fused; 20, interior of the pedicle valve, ×1, showing the muscle scars, paratype USNM 148394n; 21, anterior view of the interior, ×2, showing median septum, and long crura, paratype USNM 148394h; 23, 24, interior of the brachial valve, ×1, and tilted ×3, showing the fused hinge plate, median septum, and oval muscle field, paratype USNM 148394o. [Cherry Canyon Formation (Getaway Member), USNM 728.]

Phrenophoria pinguis (Girty): 25–28, Anterior, dorsal, ventral, and side views of an imperfect specimen, ×1, holotype USNM 118570. [Bell Canyon Formation (Pinery Member), USGS 2930 (green).]

29, 30, Posteriorly tilted and interior views of a brachial valve, ×1, hypotype USNM 154755; 31, 32, posteriorly tilted and interior views of the preceding brachial valve, ×2, showing the median septum, fused hinge plate, and crura. [Capitan Formation, USNM 748a.]

Phrenophoria planifrons, new species: 33–37, Dorsal, posterior, ventral, side, and anterior views, ×1, of the holotype USNM 148378a; 38, anterior of the preceding specimen, ×2, showing the growth increments. [Cathedral Mountain Formation, USNM 702b.]

Phrenophoria planiventra, new species: 39–43, Ventral, anterior, side, dorsal, and posterior views, ×1, holotype USNM 148381a; 44, side view of the holotype, ×2, [Road Canyon Formation, USNM 703.]

Phrenophoria cf. P. planiventra, new species: 45–49, Ventral, anterior, side, posterior, and dorsal views of a complete specimen, ×1, figured specimen USNM 154754; 50, beak of the preceding specimen, ×3, showing conjunct deltidial plates. [Road Canyon Formation, USNM 707e.]

Phrenophoria vetula, new species: 51–55, Posterior, side, anterior, ventral, and dorsal views, ×1, holotype USNM 154757a; 56, posterior of the brachial valve, ×2, showing the fused hinge plate, paratype USNM 154757b (see Plate 519: figure 38 for further enlargement). [Cathedral Mountain Formation, USNM 721u.]

57–59, Laterally tilted, posteriorly tilted, and interior views of a brachial valve, ×3, showing median septum, hinge plate, and crura, paratype USNM 148373. [Cathedral Mountain Formation, USNM 702.]

PLATE 518.—Phrenophoria.

PLATE 519

Phrenophoria, Tautosia, Cenorhynchia, and Holosia

Phrenophoria repugnans, new species: 1, 2, Dorsal, anterior, and side views of two immature paratypes, ×1, USNM 152829b, c; 7–9, side, anterior, and dorsal views of a complete specimen, ×2, paratype USNM 152829d; 10, ventral, posterior, side, anterior, and dorsal views, ×1, of the holotype USNM 152829g; 11–14, ventral, posterior, side, anterior, and dorsal views, ×1, and dorsal, side, and anterior views, ×2, paratype USNM 152829e; 15, 16, anterior and laterally tilted views of the interior, ×1.5, paratype USNM 154760; 17, 18, same views as preceding, ×4.5, showing median septum and long crura. [Bone Spring Formation, AMNH 591.]

3–6, Dorsal, posterior, side, anterior, and dorsal views, ×1, and anterior, dorsal, and side views, ×2, o£ a complete specimen, paratype USNM 154759a. [Skinner Ranch Formation (Sullivan Peak Member), USNM 722-1.]

Phrenophoria anterocostata, new species: 19, Ventral, posterior, side, anterior, and dorsal views, ×1, paratype USNM 153486b; 20–23, ventral, posterior, side; anterior, and dorsal views, ×1, and dorsal, anterior, and side views, ×2, holotype USNM 153486a, [Cathedral Mountain Formation, USNM 721u.]

Tautosia elegans (Girty): 24, Interior of the brachial valve, ×3, showing the hinge plate, hypotype USNM 154758. [Bell Canyon Formation (Lamar Member), USNM 728p.

Cenorhynchia unicoslata, new species: 25–28, Ventral, posterior, side, anterior, and dorsal views, ×1, and anterior, dorsal, and side views, ×1.5, holotype USNM 153485a; 29, ventral, posterior, side, anterior, and dorsal views, ×1, paratype USNM 153485b; 30, interior of the pedicle valve, ×2, showing disjunct deltidial plates, paratype USNM 153485e; 31, 32, interior and interior posteriorly tilted views, ×2, showing the fused hinge plate and small septum, paratype USNM 153485f; 33, partial side view of a specimen, ×2, showing short median septum and cardinalia, paratype USNM 153485g; 34, interior of another brachial valve, ×3, Showing hinge plate and median septum, paratype USNM 153485h. [Cathedral Mountain Formation, USNM 721u.]

Phrenophoria species 1: 35, 36, Exterior and interior of the brachial valve, ×1, figured specimen USNM 148390; 37, interior of the preceding specimen, ×2, showing the hinge plate. [Skinner Ranch Formation (Sullivan Peak Member), USNM 707d.]

Phrenophoria vetula, new species: 38, Interior of a fragmentary brachial valve, ×5, showing the nearly completely fused hinge plate (see plate 518: figure 56), paratype USNM 154757b. [Cathedral Mountain Formation, USNM 721u.]

Holosia species 1: 39, 40, Exterior and interior of a brachial valve, ×1, showing hinge plate, figured specimen USNM 154761. [Word Formation (China Tank Member), USNM 706c.]

PLATE 519.—Phrenophoria, Tautosia, Cenorhynchia, and Holosia

PLATE 520

Cenorhynchia, Pontisia, Leiorhynchoidea, Strigirhynchia, Ptygmactrum, and Anteridocus

Cenorhynchia pentagonalis, new species: 1–4, Ventral, posterior, side, anterior, and dorsal views, ×1, and side, anterior, and dorsal views, ×2, holotype USNM 152814a; 5, dorsal view, ×1, of a paratype USNM 152814b; 6–8, dorsal, side and anterior views of a young specimen, ×1, paratype USNM 152814j; 9, posterior of a brachial valve, ×4, showing cardinalia, paratype USNM 152814g; 10, lateral view of the interior, ×4, showing median septum and crura, paratype USNM 152814f. [Word Formation (China Tank Member), USNM 706c.]

49, Interior, ×6, showing dental plates, hinge plate, and median septum, paratype USNM 152814d. [Word Formation (China Tank Member), USNM 706c.]

Pontisia wolfcampensis, new species: 11, 12, Ventral, posterior, side, anterior, and dorsal views of an immature specimen and a young adult, ×1, paratypes USNM 154764a, b; 13–16, ventral, posterior, side, anterior, and dorsal views, ×1, and dorsal, side, and anterior views, ×2, holotype USNM 154764c; 17, interior of the brachial valve, ×3, showing hinge plate and muscle scars, paratype USNM 154764e; 18, anterior view of the cardinalia, ×3, showing the crura, paratype USNM 154764d. [Neal Ranch Formation, USNM 727e.]

Leiorhynchoidea species unidentified: 19, 20, Interior and exterior of a pedicle valve, ×1, figured specimen USNM 152867. [Bone Spring Formation, USNM 728f.]

21, 22, Interior and exterior of the brachial valve, ×2, figured specimen USNM 152868. [Bone Spring Formation, USNM 728h.]

Pontisia parva, new species: 23, 28, Ventral, posterior, side, anterior, and dorsal views, ×1, of two paratypes USNM 154928a, c; 24–27, ventral, posterior, side, anterior, and dorsal views, ×1, and dorsal, anterior, and side views, ×2, holotype USNM 154928b; 29, interior of the brachial valve, ×4, paratype USNM 154928d; 30, interior of the pedicle valve, ×4, showing conjunct deltidial plates, paratype USNM 154928e. [Neal Ranch Formation, USNM 727e.]

Pontisia kingi, new species: 31–34, Ventral, posterior, side, anterior, and dorsal views, ×1, and side, anterior, and dorsal views, ×2, paratype USNM 154763a. [Neal Ranch Formation, USNM 727e.]

Strigirhynchia indentata (Shumard): 35–39, Posterior, ventral, anterior, dorsal, and side views of a complete specimen, ×1, hypotype USNM 155107. [Bell Canyon Formation (Lamar Member), USNM 728p.]

Ptygmactrum extensum, new species: 40–44, Posterior, anterior, side, ventral, and dorsal views of a complete specimen, ×4, paratype USNM 148321c. [Road Canyon Formation, USNM 703d.]

Anteridocus bicostatus, new species: 45–48, Posterior, anterior, side, dorsal, and ventral views, ×1, and side, dorsal, and anterior views, ×2, paratype USNM 152841. [Carlsbad Formation?, AMNH 417.]

Pontisia ventricola, new species: 50–52, Side, anterior, and dorsal views of a complete specimen, ×2, paratype USNM 152860j; 53–55, anterior, side, and dorsal views of a large adult, ×2, holotype USNM 152860m (for natural size views see Plate 536: figure 36). [Hess Formation (top), USNM 726n.]

PLATE 520.—Cenorhynchia, Pontisia, Leiorhynchoidea, Strigirhynchia, Ptygmactrum, and Anteridocus.

PLATE 521

Phrenophoria, Petasmatherus, Tautosia, Strigirhynchia, Aphaurosia, Cenorhynchia, and Anteridocus

Phrenophoria incomitata, new species: 1–6, Ventral, side, posterior, anterior, and dorsal views, ×1, and dorsal view, ×2, holotype USNM 152827a; 7, lateral view into the holotype, ×3, showing the hinge plate; 8, 9, interior of the pedicle valve, ×1.5, ×4.5, showing dental plates, paratype USNM 152827b. [Bone Spring Formation (Cutoff Member), AMNH 678.]

Petasmatherus pumilus, new species: 10–15, Dorsal view, ×1, and anterior, posterior, side, ventral, and dorsal views, ×2, paratype USNM 154766a; 16–21, dorsal view, ×1, and dorsal, ventral, side, posterior, and anterior views, ×2, paratype USNM 154766b. [Road Canyon Formation, USNM 732j.]

Tautosia angulata, new species: 22–29, Posterior, ventral, dorsal, anterior, and side views, ×1, and dorsal, side, and anterior views, ×2, holotype USNM 154767. [Road Canyon Formation, USNM 732j.]

Strigirhynchia indentata (Shumard): 30, Exterior showing ornament and foramen, ×2, hypotype USNM 154771; 31, interior of the preceding specimen, ×3, showing the cardinalia. [Bell Canyon Formation (Lamar Member), USNM 728p.]

Aphaurosia rotundata, new species: 32–36, Dorsal view, ×1, and anterior, side, ventral, and dorsal views, ×2, paratype USNM 154509i; 37–41, dorsal view, ×1, and ventral, side, anterior, and dorsal views, ×2, paratype USNM 154509j. [Bell Canyon Formation (Lamar Member), USNM 728p.]

Cenorhynchia transversa, new species: 42–45, Dorsal, anterior, and side views, ×1, and dorsal view, ×2, holotype USNM 154769; 46, 47, interior and posteriorly tilted views of the brachial valve, ×3, showing cardinalia and median septum. [Road Canyon Formation, USNM 732j.]

Cenorhynchia camerata, new species: 48–52, Anterior, dorsal, side, posterior, and ventral views, ×1, holotype USNM 155069d (for enlarged views, see figures 62–64); 53–57, dorsal, ventral, anterior, posterior, and side views, ×1, paratype USNM 155069a; 62–64, side, anterior, and dorsal views, ×2, holotype USNM 155069d (for ×1, views, see figures 48–52). [Neal Ranch Formation (bed 4), USNM 727e.]

Anteridocus triangulatus, new species: 58–61, Dorsal view, ×1, and dorsal, anterior, and side views, ×2, holotype USNM 154768. [Road Canyon Formation, USNM 732j.]

Phrenophoria perplexa, new species: 65, 66, Ventral and dorsal views of an incomplete specimen, ×1, paratype USNM 154770a; 67, interior of the preceding specimen, ×2; 68, 69, exterior and interior of another brachial valve, ×1, paratype USNM 154770b; 70, the preceding specimen, ×2, showing hinge plate; 71, interior of another brachial valve, ×2, showing the hinge plate, paratype USNM 154770c; 72, interior views of pedicle valve, ×2, showing muscle scars and conjunct deltidial plates, paratype USNM 154770d. [Bell Canyon Formation (Rader Member), USNM 725g.]

73, Interior of another pedicle valve, ×2, showing muscle field and conjunct deltidial plates, paratype USNM 154665a. [Bell Canyon Formation (Rader Member), USNM 740a.]

PLATE 521.—Phrenophoria, Petasmatherus, Tautosia, Strigirhynchia, Aphaurosia, Cenorhynchia, and Anteridocus.

PLATE 522

Phrenophoria

Phrenophoria? nudumbona, new species: 1–3, Posterior, anterior, side, ventral, and dorsal views, ×1, and anterior and dorsal views, ×1.5, holotype USNM 148373. [Road Canyon Formation, USNM 703d.]

Phrenophoria compressa, new species: 4–7, Anterior, posterior, side, ventral, and dorsal views, ×1, and anterior, dorsal, and side views, ×2, holotype USNM 153489. [Road Canyon Formation, USNM 706f.]

Phrenophoria pinguis (Girty): 8–13, Side, ventral, posterior, anterior, and dorsal views, ×1, and dorsal view, ×2, hypotype USNM 154784. [Bell Canyon Formation (Hegler Member), USNM 732a.]

Phrenophoria subcarinata Cooper and Grant: 14, 15, Dorsal view, ×1, and posterior view, ×1.5, showing median septum, hypotype USNM 154785. [Word Formation (Willis Ranch Member), USNM 703e.]

16, Ventral, posterior, side, anterior, and dorsal views of a complete specimen, ×1, paratype USNM 148385c; 50, posterior of the preceding specimen, ×3, showing foramen and conjunct deltidial plates; 17–21, posterior, anterior, side, dorsal, and ventral views, ×1, holotype USNM 148385e; 30–34, posterior, anterior, dorsal, ventral, and side views of another complete specimen, ×1, paratype USNM 148385d; 35, interior of the pedicle valve, ×2, showing conjunct deltidial plates and teeth, paratype USNM 148385i; 36–39, interior and interior laterally tilted views of the brachial valve, ×1, and laterally tilted and interior views of the same specimen, ×3, showing the hinge plate, crura and median septum, paratype USNM 148385g; 40, 41, interior of another pedicle valve, ×1, ×3, paratype USNM 148385h; 46–49, Interior and laterally tilted views, ×1, and the same views, ×3, showing the cardinalia, paratype USNM 148385f. [Word Formation (lens between Willis Ranch and Appel Ranch members), USNM 706b.]

22–24, Dorsal, anterior, and side views, ×1, paratype USNM 148387a; 42–45, interior, ×1, and laterally tilted, interior, and posteriorly tilted views, ×2, of a brachial valve, showing cardinalia and median septum, paratype USNM 154783. [Word Formation (China Tank Member), USNM 706c.]

25–29, Anterior, side, dorsal, ventral, and posterior views, ×1, paratype USNM 152830a. [Word Formation (Appel Ranch Member), USNM 719z.]

PLATE 522.—Phrenophoria.

PLATE 523

Phrenophoria, Holosia, and Tautosia

Phrenophoria ventricosa, new species: 1–4, Dorsal, posterior, side, anterior, and ventral views, ×1, and dorsal, anterior, and side views, ×2, paratype USNM 148382f; 5, dorsal, posterior, side, anterior, and ventral views, ×1, of another paratype USNM 148382e; 6, ventral, posterior, side, anterior, and dorsal views, ×1, paratype USNM 148382b; 7–10, ventral, posterior, side, anterior, and dorsal views, ×1, and side, anterior, and dorsal views, ×2, showing color markings, holotype USNM 148382a; 11, side view of a brachial valve, ×3, showing crus, paratype USNM 148382g. [Road Canyon Formation, USNM 703d.]

Holosia ovalis, new species: 12–16, Posterior, anterior, side, dorsal, and ventral views of a specimen with boring, ×1, holotype USNM 152833c; 17, dorsal view, ×1, of a paratype USNM 152833a; 18–21, dorsal, ventral, side, and posterior views, ×1, of another paratype USNM 152833b; 22, 23, Interior of a poorly preserved brachial valve, ×1, ×2, showing the hinge plate and median septum, paratype USNM 152833d. [Road Canyon Formation, USNM 707e.]

Holosia ovoidea, new species: 24–28, Posterior, anterior, side, ventral, and dorsal views, ×1, holotype USNM 148398. [Cherry Canyon Formation (Getaway Member), USNM 728.]

Holosia regularis, new species: 29, Ventral, posterior, side, anterior, and dorsal views, ×1, holotype USNM 152834; 30, interior of the brachial valve of the holotype, ×2; 31, 32, posteriorly tilted and interior views of the brachial valve of the holotype, ×2, showing hinge plate and median septum. [Bell Canyon Formation (Rader Member), AMNH 401.]

Tautosia elegans (Girty): 33–37, Anterior, ventral, posterior, dorsal, and side views of a complete specimen, ×1, holotype USNM 118565. [Capitan Formation, USGS 2926 (green).]

38, 39, Ventral, posterior, side, anterior, and dorsal views, ×1, hypotypes USNM 154791a, b; 40–42, broken specimen revealing the cardinalia, ×1, and laterally tilted and posterior views, ×3, of the same specimen, showing the long crura and short hinge plate, hypotype USNM 154791c; 43–46, interior and posteriorly tilted views, ×2, and the same views, ×4, showing hinge plate, hypotype USNM 15479Id; 47–49, interior of the pedicle valve, ×1.5, and interior and posteriorly tilted views of the same specimen, ×3, showing conjunct deltidial plates and dental plates, hypotype USNM 154791e. [Bell Canyon Formation (Lamar Member), USNM 725e.]

50, 51, Ventral, posterior, side, anterior, and dorsal views, ×1, hypotypes USNM 154790c, d. [Bell Canyon Formation (Lamar Member), USNM 738b.]

PLATE 523.—Phrenophoria, Holosia, and Tautosia.

PLATE 524

Tautosia and Phrenophoria

Tautosia expansa, new species: 1, 2, Ventral, posterior, side, anterior, and dorsal views, ×1, of two paratypes USNM 148589e, c; 3–6, ventral, posterior, side, anterior, and dorsal views, ×1, and anterior, dorsal, and side views, ×2, holotype USNM 148589d; 7–9, ventral and laterally tilted views, ×1.5, and ventral view, ×3, of a specimen with pedicle valve beak removed to show cardinalia, paratype USNM 148589g. [Bone Spring Formation (Cutoff Member), USNM 747.]

Phrenophoria vetula, new species: 10–14, Anterior, posterior, side, ventral, and dorsal views, ×1, paratype USNM 152832. [Cathedral Mountain Formation, USNM 702.]

Tautosia fastigiata Cooper and Grant: 15, Two immature hypotypes, ×1, USNM 148342c, e; 18–22, anterior, dorsal, side, posterior, and ventral views, ×1, hypotype USNM 154792a; 23, 49, interior and posteriorly tilted views of a pedicle valve, ×1, ×1.5, showing the muscle scars, hypotype USNM 154793d; 24–28, anterior, posterior, side, dorsal, and ventral views of a large adult, ×1, hypotype USNM 154792c; 31–35, dorsal, ventral, side, anterior, and posterior views, ×1, of another complete specimen, hypotype USNM 154792b; 36–39, anterior, dorsal, posterior, and ventral views, ×1, of a large complete specimen, holotype, USNM 148345f; 48, left flank of preceding specimen, ×2, showing notches at end of costae; 41–45, ventral, dorsal, side, posterior, and anterior views, ×1, of a large adult, paratype USNM 148345e; 47, anterolateral view of a broken specimen, ×2, showing the crura, hypotype USNM 154793f; 51, 52, partial side and ventral views of another broken specimen, ×2, showing the cardinalia, hypotype USNM 154793a; 53, anterior view of the interior, ×2, showing median septum and crura, hypotype USNM 154793e. [Cathedral Mountain Formation, USNM 702b.]

16, Dorsal, anterior, and side views of another immature individual, ×1, showing its compressed form, hypotype USNM 154794c; 17, 46, dorsal, anterior, and side views, ×1, and dorsal view, ×3, of another compressed young individual, showing conjunct deltidial plates, hypotype USNM 794d; 50, immature specimen, ×3, without deltidial plates, hypotype USNM 154794a. [Cathedral Mountain Formation, USNM 726x.]

29, 30, Dorsal view of a young adult, ×1, and its beak, ×3, showing conjunct deltidial plates, hypotype USNM 154795. [Cathedral Mountain Formation, USNM 702.]

40, Ventral view of a specimen with gastropod? boring, ×1, hypotype USNM 154796a. [Cathedral Mountain Formation, AMNH 500L ═ 702b.]

PLATE 524.—Tautosia and Phrenophoria.

PLATE 525

Tautosia, Phrenophoria, and Acolosia

Tautosia fastigiata Cooper and Grant: 1, Ventral view of the cardinalia, ×4, showing crura, paratype USNM 154793c. [Cathedral Mountain Formation, USNM 702b.]

Tautosia galbina, new species: 2, Ventral, posterior, side, anterior, and dorsal views, ×1, paratype USNM 154798a; 3–6, ventral, posterior, side, anterior, and dorsal views, ×1, and side, anterior, and dorsal views, ×2, holotype USNM 154798b. [Road Canyon Formation, USNM 722g.]

7, 8, Ventral, posterior, side, anterior, and dorsal views, ×1, paratypes USNM 148352a, e; 9–11, anterior, side, and dorsal views, ×2, of another complete specimen, paratype USNM 148352d; 12, specimen with beak broken away to show crura, ×3, paratype USNM 154797. [Road Canyon Formation, USNM 707e.]

Phrenophoria irregularis, new species: 13, 14, Internal mold of a specimen, ×1, showing the dental plates and median septum, paratype USNM 152836c; 15, posterior of the preceding specimen, ×1.5, showing septa; 16–23, dorsal, posterior, ventral, anterior, and side views, ×1, and anterior, side, and dorsal views, ×1.5, holotype USNM 152836a; 24, interior of the pedicle valve, ×2, showing the muscle scars, paratype USNM 152836d; 25, posteriorly tilted view of the brachial valve, ×2, showing the hinge plate and median septum, paratype USNM 152836e. [Cherry Canyon Formation (Getaway Member), AMNH 512.]

Tautosia lenumbona (Stehli): 26–29, Ventral, posterior, side, anterior, and dorsal views, ×1, and dorsal, anterior, and side views, ×2, of a complete specimen, hypotype USNM 152837. [Bone Spring Formation, AMNH 625.]

30, 31, Anteriorly tilted view, ×2, and interior view, ×4, of the pedicle valve, showing disjunct deltidial plates and traces of the muscle scars, hypotype USNM 154799a; 32, 33, laterally tilted and interior views of the brachial valve, ×3, showing the hinge plate and median septum, hypotype USNM 155105a; 34, partial side view, ×3, showing hinge plate and crura, hypotype USNM 155105b; 35, interior of a brachial valve, ×3, showing septum, hypotype USNM 155105c. [Bone Spring Formation, USNM 728f.]

Tautosia magnisepta (Stehli): 36, 37, Interior of the brachial valve, ×2, ×4, showing divided hinge plate and median septum, hypotype USNM 154800. [Bone Spring Formation, AMNH 629.]

38–41, Dorsal, posterior, side, anterior, and ventral views, ×1, and dorsal, anterior, and side views, ×2, of a complete specimen, hypotype USNM 148355a; 42, 43, laterally tilted and interior views of the brachial valve, ×2, showing the median septum and undivided hinge plate, hypotype USNM 148355d; 44, interior of the pedicle valve, ×1, hypotype USNM 148355c; 45, interior of the pedicle valve, ×2, showing disjunct deltidial plates and muscle scars, hypotype USNM 148355b. [Bone Spring Formation, USNM 728f.]

Tautosia podistra, new species: 46, Ventral, posterior, side, anterior, and dorsal views, ×1, holotype USNM 152839c; 47–50, ventral, posterior, side, anterior, and dorsal views, ×1, and dorsal, side, and anterior views, ×2, paratype USNM 152839e; 51, interior of the brachial valve, ×4, showing hinge plate and median septum, paratype USNM 152839g. [Skinner Ranch Formation (Sullivan Peak Member), USNM 707-1.]

Acolosia magna, new species: 52–55, Ventral, posterior, side, anterior, and dorsal views, ×1, and anterior, dorsal, and side views, ×3, holotype USNM 148207. [Skinner Ranch Formation (Decie Ranch Member), USNM 714t.]

PLATE 525.—Tautosia, Phrenophoria, and Acolosia.

PLATE 526

Tautosia

Tautosia pulchra, new species: 1, Dorsal views of three immature paratypes, ×1, USNM 148368b, c, f; 13–16, ventral, posterior, side, anterior, and dorsal views, ×1, of four paratypes USNM 148368d, h, g and 154801c; 17–20, interior, laterally tilted, and posteriorly tilted views of the brachial valve, ×3, showing the cardinalia, and posteriorly tilted view of the pedicle valve, ×3, showing dental plates of the same specimen, paratype USNM 154801a. [Cathedral Mountain Formation, USNM 702ent.]

2–6, Posterior, anterior, side, ventral, and dorsal views of an adult, ×1, paratype USNM 148374a; 7–12, dorsal, side, anterior, ventral, and posterior views, ×1, holotype USNM 148374b. [Cathedral Mountain Formation, USNM 702.]

Tautosia shumardiana (Girty): 21, Ventral, posterior, side, anterior, and dorsal views, ×1, of a complete specimen, hypotype USNM 148680c; 27–31, ventral, posterior, side, anterior, and dorsal views of a complete adult, ×1, hypotype USNM 148680d. [Capitan Formation, USNM 740.]

22–26, Ventral, posterior, side, anterior, and dorsal views, ×1, of a young individual, hypotype USNM 148675. [Capitan Formation, USNM 737a.]

32–36, Ventral, side, dorsal, posterior, and anterior views, ×1, holotype USNM 118566a. [Capitan Formation, USGS 2926 (green).]

37–41, Dorsal, anterior, posterior, side, and ventral views of a large adult, ×1, hypotype USNM 154804. [Capitan Formation, USNM 725-1.]

42, 43, Exterior and interior of a pedicle valve, ×1, hypotype USNM 154805. [Bell Canyon Formation (Hegler Member), AMNH 524.]

44, 45, Posteriorly tilted view, ×1, and interior view, ×2, of another pedicle valve, hypotype USNM 154803a; 46, ventral view of a specimen with beak removed to show hinge plate and crura, ×2, hypotype USNM 154803c; 47–49, ventral view of another specimen broken to show the cardinalia, ×1, and ventral and laterally tilted views of the same specimen, ×3, showing a divided hinge plate and long crura, hypotype USNM 154803b; 50, posterior view of another brachial valve, ×5, showing the posteriorly fused hinge plate and long crura, hypotype USNM 154803d; 51, partial side view of a broken specimen, ×3, showing median septum and crura, hypotype USNM 154802b. [Bell Canyon Formation (Lamar Member), USNM 725e.]

PLATE 526.—Tautosia.

PLATE 527

Tautosia and Wellerella

Tautosia transenna, new species: 1, Dorsal views of two immature paratypes, ×1, USNM 148402c, d; 13, 14, ventral, posterior, side, anterior, and dorsal views, ×1, and anterior view, ×2, showing the notched costae, holotype USNM 148402e; 15, ventral, posterior, side, anterior, and dorsal views, ×1, of a paratype USNM 154808a; 21, interior of the pedicle valve, ×2, showing conjunct deltidial plates and muscle scars, paratype USNM 154808b; 27–29, interior posteriorly tilted, interior, and laterally tilted views of the brachial valve, ×5, showing fused hinge plate, median septum, and crura, paratype USNM 154808c. [Word Formation (lens between Willis Ranch and Appel Ranch members), USNM 706b.]

2–6, Posterior, anterior, side, ventral, and dorsal views, ×1, of an obese specimen, paratype USNM 148409e; 16, 30, 31, side, dorsal, and anterior views of another complete specimen, ×1, paratype USNM 154807a; 17, 18, laterally tilted and dorsal views of a specimen with part of brachial valve removed to show crura, ×2, paratype USNM 154807b; 19, 20, laterally tilted and interior views, ×4, showing long crura and fused hinge plate, paratype USNM 154807c; 22, 23, interior of the pedicle valve, ×1.5, and ×4.5, showing conjunct deltidial plates, paratype USNM 154807d; 24, anterior view, ×5, showing median septum, crura, and hinge plate, USNM 154807e. [Cherry Canyon Formation (Getaway Member), USNM 728.]

7–12, Side, posterior, ventral, dorsal, and anterior views, ×1, and dorsal view, ×2, paratype USNM 154809a; 25, 26, laterally tilted and interior views, ×3, of a brachial valve with fused hinge plate, paratype USNM 154809b. [Word Formation (Willis Ranch Member), USNM 706e.]

Wellerella girtyi seorsa, new subspecies: 32, 33, Ventral, posterior, side, anterior, and dorsal views, ×1, paratype USNM 148582f and holotype USNM 148582g; 34–36, interior, and posteriorly tilted views, ×1.5, and posterior, ×3, of the pedicle valve, showing conjunct deltidial plates, paratype USNM 148582h; 37–39, posteriorly tilted, laterally tilted, and interior views of the brachial valve, ×3, showing crura and fused hinge plate, paratype USNM 148582i. [Cherry Canyon Formation (Getaway Member), USNM 728.]

PLATE 527.—Tautosia and Wellerella.

PLATE 528

Wellerella

Wellerella girtyi girtyi, new subspecies: 1–3, Ventral, anterior, side, and dorsal views, ×1, of three immature paratypes USNM 154732a-c; 4–8, posterior, side, anterior, ventral, and dorsal views, ×1, of an adult, paratype USNM 148565j; 9–11, ventral, posterior, side, anterior, and dorsal views, ×1, of three young adults, paratypes USNM 154732d-f; 12–16, ventral, posterior, side, anterior, and dorsal views of an adult, ×1, paratype USNM 154732g; 17–21, ventral, posterior, side, anterior, and dorsal views, ×1, of another adult, paratype USNM 154732h; 22–26, ventral, posterior, side, anterior, and dorsal views, ×1, of the holotype, USNM 154732i; 27, 28, interior of an immature pedicle valve, ×3, ×6, showing incipient deltidial plates, paratype USNM 154811a; 29, 30, interior of an immature brachial valve, ×3, ×6, showing early beginnings of the hinge plate, paratype USNM 154811b; 31, 32, ventral view of an immature specimen, ×3, ×6, showing the cardinalia, paratype USNM 154811c; 33–35, posteriorly tilted view, ×3, ×6, and interior view, ×3, of an immature individual, showing a well formed undivided hinge plate, paratype USNM 154811d; 36–38, interior and posteriorly tilted views, ×6, and interior view, ×3, of a brachial valve, showing immature stage of the cardinalia, paratype USNM 154811e; 39, 40, interior and posteriorly tilted views of another immature brachial valve, ×5, showing incipient hinge plate, paratype USNM 154811f; 41, 42, posteriorly tilted and interior views, ×3, showing hinge plate, crura, and median ridge, paratype USNM 154732j; 45, interior of the pedicle valve, ×1.5, paratype USNM 154732k; 46, dorsal view of the cardinalia, ×4, showing incipient median ridge, crura, and hinge plate, paratype USNM 154811g. [Word Formation (Willis Ranch Member), USNM 706e.]

43, 44, Interior of the pedicle valve, ×1.5, ×4.5, showing conjunct deltidial plates, paratype USNM 154810. [Word Formation (Willis Ranch Member), USNM 706.]

Wellerella nitidula, new species: 47–50, Ventral, posterior, side, anterior, and dorsal views, ×1, and anterior, side, and dorsal views, ×2, of a complete specimen, paratype USNM 154812. [Bone Spring Formation, AMNH 492.]

51–54, Ventral, posterior, side, anterior, and dorsal views, ×1, and anterior, side, and dorsal views, ×2, holotype USNM 152866c; 55, 56, ventral, posterior, side, anterior, and dorsal views, ×1, of two adult paratypes USNM 152866f, d; 57–59, side, dorsal, and anterior views of another complete specimen, ×2, paratype USNM 152866a; 60, interior of a pedicle valve without deltidial plates, ×1.5, paratype USNM 152866g; 61, dorsal view of the interior, ×3, showing the long crura, paratype USNM 152866i; 62, lateral view of the interior of another specimen, ×3, showing the crura, paratype USNM 152866h. [Bone Spring Formation, AMNH 591.]

PLATE 528.—Wellerella.

PLATE 529

Anteridocus, Pontisia, and Antronaria

Anteridocus bicostatus, new species: 1, Posterior, anterior, side, ventral, and dorsal views, ×1, holotype USNM 152842a. [Bell Canyon Formation (Lamar Member), USNM 738b.]

2, Anterolateral view, ×3, showing the crura but no septum, paratype USNM 154814. [Bell Canyon Formation (Lamar Member), AMNH 347.]

3–7, Posterior, anterior, side, ventral, and dorsal views, ×1, of a complete specimen, paratype USNM 154813. [Bone Spring Formation (Cutoff Member), AMNH 678.]

Pontisia costata, new species: 8–11, Ventral, posterior, side, anterior, and dorsal views, ×1, and side, dorsal, and anterior views, ×2, paratype USNM 154816r; 12–15, ventral, posterior, side, anterior, and dorsal views, ×1, and dorsal, side, and anterior views, ×2, paratype USNM 152843b; 16–19, ventral, posterior, side, anterior, and dorsal views, ×1, and side, anterior, and dorsal views, ×2, holotype USNM 152843a; 20, interior of the pedicle valve, ×1.5, paratype USNM 154816a; 21, posterior of the brachial valve, ×6, paratype USNM 154816b; 22, 23, interior of the brachial valve, ×3 and ×4.5, showing cardinalia, paratype USNM 154816c. [Skinner Ranch Formation (base), USNM 705a.]

24, 25, Posteriorly tilted and interior views, ×3, showing cardinalia, paratype USNM 154815b; 26, side, anterior, dorsal, and ventral views, ×1, paratype USNM 154815a. [Skinner Ranch Formation, USNM 724q.]

Antronaria dissona, new species: 27–31, Dorsal, posterior, side, anterior, and ventral views, ×1, paratype USNM 154818. [Skinner Ranch Formation (base), locality 720e.]

32–36, Anterior, posterior, side, dorsal, and ventral views of a complete specimen, ×1, paratype USNM 148766a; 42–46, posterior, anterior, side, ventral, and dorsal views of a complete specimen, ×1, paratype USNM 148766b. [Skinner Ranch Formation (base), USNM 705a.]

37–41, Posterior, ventral, side, dorsal, and anterior views, ×1, paratype USNM 148774a. [Skinner Ranch Formation (Decie Ranch Member), USNM 707w.]

47–49, Anterior, dorsal, and side views of a large individual, ×1, paratype USNM 154820b; 63, partial side view of a broken specimen, ×1, showing the crura, paratype USNM 154820c; 50–54, anterior, side, ventral, dorsal, and posterior views, ×1, holotype USNM 154820a. [Bone Spring Formation, AMNH 492.]

55, Dorsal view of a small specimen, ×1, paratype USNM 148776b; 56–59, ventral, side, dorsal, and anterior views, ×1, paratype USNM 154817. [Skinner Ranch Formation (lower), USNM 711p.]

60, Specimen with broken beak, ×2, showing the hinge plate and crura, paratype USNM 154819a; 61, anterior view of the interior, ×2, showing the cardinalia, paratype USNM 154819b; 62, brachial valve, ×2, showing the hinge plate, paratype USNM 154819c. [Bone Spring Formation, 728f.]

Pontisia franklinensis, new species: 64, 65, Ventral, posterior, side, anterior, and dorsal views, ×1, paratypes USNM 152846c, b; 66–69, ventral, posterior, side, anterior, and dorsal views, ×1, and dorsal, side, and anterior views, ×2, holotype USNM 152846a; 70, anterior view of the interior, ×3, showing the cardinalia, paratype USNM 152846f. [Alacran Mountain Formation, USNM 712m.]

PLATE 529.—Anteridocus, Pontisia, and Antronaria.

PLATE 530

Antronaria and Pontisia

Antronaria emarginata, new species: 1–5, Posterior, anterior, side, ventral, and dorsal views, ×1, paratype USNM 152844. [Skinner Ranch Formation (Decie Ranch Member), USNM 707a.]

6–10, Dorsal, ventral, posterior, anterior, and side views, ×1, paratype USNM 148662. [Skinner Ranch Formation (Sullivan Peak Member), USNM 707.]

11–15, Anterior, dorsal, side, posterior, and ventral views, ×1, holotype USNM 154838a. [Skinner Ranch Formation (Decie Ranch Member), USNM 727u.]

Pontisia kingi, new species: 16, Ventral, posterior, side, anterior, and dorsal views, ×1, paratype USNM 152848a; 17, 18, ventral, posterior, side, anterior, and dorsal views, ×1, and anterior view, ×2, holotype USNM 152848b. [Neal Ranch Formation (bed 4), USNM 721g.]

19–22, Posterior, anterior, side, ventral, and dorsal views, ×1, and side, dorsal, and anterior views, ×2, paratype USNM 148593d; 28–30, interior and posteriorly and laterally tilted views, ×3, showing the cardinalia, paratype USNM 154836b; 31, interior of the pedicle valve, ×3, showing the teeth, paratype USNM 154836a; 32, interior and posteriorly tilted views of the posterior of a brachial valve, ×3, showing the cardinalia, paratype USNM 154836d. [Neal Ranch Formation (bed 4), USNM 701d.]

23, Posterior, anterior, side, ventral, and dorsal views, ×1, paratype USNM 148598; 24, interior of the pedicle valve, ×1.5, paratype USNM 148597; 25, 26, interior and laterally tilted views, ×3, of the brachial valve of the preceding specimen; 27, dorsal, anterior, and side views of the preceding specimen, ×1. [Neal Ranch Formation (bed 4), USNM 701-1.]

Pontisia longicosta (Stehli): 33–36, Ventral, posterior, side, anterior, and dorsal views, ×1, and dorsal, side, and anterior views, ×3, hypotype USNM 154835a; 37–39, ventral, posterior, side, anterior, and dorsal views, ×1, and dorsal, anterior, and side views, ×3, hypotype USNM 154835b; 40, interior of the pedicle valve, ×3, showing disjunct deltidial plates, hypotype USNM 154835c; 41, posteriorly tilted view of the pedicle valve interior, ×6, showing dental plates and disjunct deltidial plates, hypotype USNM 154835f; 42–44, posteriorly tilted, interior, and laterally tilted views of the brachial valve, ×6, showing hinge plate, hypotype USNM 154835d; 45, anterior view of another brachial valve, ×6, showing the cardinalia, hypotype USNM 154835e. [Bone Spring Formation, USNM 728f.]

PLATE 530.—Antronaria and Pontisia.

PLATE 531

Antronaria and Pontisia

Pontisia magnicostata, new species: 1–5, Dorsal, posterior, side, anterior, and ventral views, ×1, holotype USNM 152850a; 6–8, interior, laterally tilted, and anterior views of the brachial valve interior, ×2, showing undivided hinge plate and thick, low median ridge, paratype USNM 152850c. [Neal Ranch Formation (beds 9–12 of Cooper), USNM 722w.]

Antronaria indentata, new species: 9–13, Posterior, anterior, side, ventral, and dorsal views of a complete specimen, ×1, holotype USNM 154839a; 14–18, posterior, anterior, ventral, dorsal, and side views of an obese specimen, ×1, hypotype USNM 154839b; 19, 20, interior of the pedicle valve, ×1.5, ×2, showing teeth and disjunct deltidial plates, hypotype USNM 152851a; 21, 22, interior of the brachial valve, ×1, ×2, paratype 152851c; 23, 24, anterior view of the interior, ×1, ×2, showing the long crura, hypotype USNM 152851b. [Bone Spring Formation, USNM 725c.]

Antronaria mesicostalis (Girty): 25–29, Dorsal, posterior, side, anterior, and ventral views, ×1, hypotype USNM 154840. [Bone Spring Formation, AMNH 697].

30–34, Dorsal, posterior, side, anterior, and ventral views, ×1, lectotype USNM 152852a. [Bone Spring Formation, North Apache Canyon, Diablo Plateau, Texas.]

35, 36, Posteriorly tilted and interior views, ×2, of the brachial valve, hypotype USNM 154841a; 37, 38, interior of another brachial valve, ×1, ×2, showing muscle scars and cardinalia, hypotype USNM 154841b. [Bone Spring Formation, AMNH 625.]

Pontisia nanas (Stehli): 39, 52, Ventral, posterior, side, anterior and dorsal views, ×1, and dorsal view, ×3, hypotype USNM 154842a; 40–43, ventral, posterior, side, anterior, and dorsal views, ×1, and dorsal, side, and anterior views, ×3, hypotype USNM 154842c; 44–47, ventral, posterior, side, anterior, and dorsal views, ×1, and side, anterior, and dorsal views, ×3, hypotype USNM 154842d; 48, 49, posteriorly tilted view, ×2, and interior views, ×4, of the pedicle valve, showing dental plates and disjunct deltidial plates, hypotype USNM 154842e; 50, 51, interior and ventral views of the brachial valve interior, ×4, showing hinge plate and crus, hypotype USNM 154842f; 53–55, laterally tilted, posteriorly tilted, and interior views of another brachial valve, ×4, showing cardinalia, hypotype USNM 154842g; 56, interior of another brachial valve, ×6, hypotype USNM 154842h; 57, anterior view of the interior, ×6, showing the long crura, hypotype USNM 154842i; 58, anterior view of a brachial valve interior, ×4, hypotype USNM 154842j. [Bone Spring Formation, USNM 728f.]

PLATE 531.—Antronaria and Pontisia.

PLATE 532

Antronaria

Antronaria specialis, new species: 1–5, Posterior, anterior, side, ventral, and dorsal views, ×1, paratype USNM 154843a; 6–10, posterior, side, anterior, ventral and dorsal views, ×1, paratype USNM 152856d; 11–15, posterior, anterior, ventral, side, and dorsal views, ×1, holotype USNM 152856f; 16–18, anterior, side, and dorsal views, ×1, of a large specimen, paratype USNM 152856g; 19, posterior view, ×4, showing foramen and conjunct deltidial plates, paratype USNM 152856d; 20, posterior view of a broken specimen, ×2, showing the long crura, paratype USNM 154843b; 21, anterior view of the interior, ×3, showing cardinalia, paratype USNM 154845f; 22, lateral view of another specimen, ×2, showing the crura, paratype USNM 154843c; 23, dorsal views, ×1, immature paratypes USNM 154844b-g. [Bone Spring Formation, AMNH 492.]

Antronaria speciosa, new species: 24, 25, Ventral, posterior, side, anterior, and dorsal views, ×1, immature paratypes USNM 154847a, b; 31–35, ventral, posterior, side, anterior, and dorsal views, ×1, of an immature specimen, paratype USNM 148682d; 36–40, ventral, posterior, side, anterior, and dorsal views, ×1, of a young adult, paratype USNM 148682f; 41–45, dorsal, posterior, anterior, side, and dorsal views of an adult, ×1, paratype USNM 154847c; 46–50, posterior, anterior, ventral, side, and dorsal views, ×1, of the holotype USNM 154847d; 51, 52, interior of the pedicle valve, ×1, ×3, showing dental plates and conjunct deltidial plates, paratype USNM 154847e; 53–55, laterally tilted and interior views, ×1, and interior views, ×3, of a brachial valve, showing hinge plate and crura, paratype USNM 154847f; 59, 60, laterally tilted and interior views of a brachial valve, ×3, showing the cardinalia, paratype USNM 154846; 61, anterior view of the interior, ×3, showing crura, paratype USNM 154847h. [Hess Formation (Taylor Ranch Member), USNM 702d.]

26–30, Posterior, side, ventral, anterior, and dorsal views of a large adult, ×1, paratype USNM 148686. [Skinner Ranch Formation (Sullivan Peak Member), USNM 729h.]

56–58, Interior and laterally tilted views, ×3, and interior view, ×1, of a brachial valve, paratype USNM 148688. [Hess Formation (Taylor Ranch Member), USNM 702e.]

PLATE 532.—Antronaria.

PLATE 533

Antronaria and Pontisia

Antronaria spectabilis, new species: 1–5, Posterior, anterior, side, ventral, and dorsal views, ×1, paratype USNM 152857d; 6, interior view, ×1, of the pedicle valve, showing dental plates and conjunct deltidial plates, paratype USNM 154854a (see also figure 34); 17–21, posterior, anterior, side, ventral, and dorsal views of a large adult, ×1, paratype USNM 152857g; 22–26, posterior, anterior, ventral, side, and dorsal views of a large individual, ×1, holotype USNM 152857i; 27, interior of another pedicle valve, ×1, paratype USNM 154854b; 28–30, interior view, ×1, and interior and laterally tilted views, ×2, showing the hinge plate, paratype USNM 154854c; 31–33, posteriorly tilted, interior, and laterally tilted views of another brachial valve, ×1, paratype USNM 154854d; 34, posterior view of the pedicle valve beak (see figure 6), ×3, showing fused deltidial plates, paratype USNM 154854a; 35–38, interior view, ×1, and interior, laterally tilted, and posteriorly tilted views, ×3, of a large brachial valve showing hinge plate and crura, paratype USNM 154854e. [Bone Spring Formation, USNM 728g.]

7–11, Posterior, anterior, side, ventral, and dorsal views, ×1, paratype USNM 152858b; 12, interior of the brachial valve, ×1, paratype USNM 154853a; 13, 14, posteriorly tilted and interior views, ×1, of another brachial valve, paratype USNM 154853b; 15, 16, posteriorly tilted and interior views of two pedicle valves, ×1, paratypes USNM 154853c, d. [Bone Spring Formation, USNM 728f.]

Pontisia stehlii stehlii Cooper and Grant: 39, Dorsal and anterior views, ×1, immature hypotypes USNM 153835i, b-e; 40, ventral, anterior, side, and dorsal views of two young adults, ×1, hypotypes USNM 153835f, g; 41–45, posterior, anterior, ventral, side, and dorsal views of a young adult, ×1, hypotype USNM 148710h; 46–50, posterior, ventral, dorsal, side, and anterior views of a fully grown specimen, ×1, hypotype USNM 148710i; 51–55, posterior, anterior, side, dorsal, and ventral views of a large adult, ×1, hypotype USNM 153835h; 56–60, ventral, posterior, side, anterior, and dorsal views, ×1, of another old adult, holotype USNM 153835a. [Road Canyon Formation, USNM 702c.]

PLATE 533.—Antronaria and Pontisia.

PLATE 534

Pontisia and Anteridocus

Pontisia stehlii stehlii Cooper and Grant: 1–5, Posterior, anterior, side, ventral, and dorsal views, ×1, hypotype USNM 154851a; 6–10, posterior, anterior, side, dorsal and ventral views of a strongly costate individual, ×1, hypotype USNM 154851b. [Road Canyon Formation, USNM 721o.]

11–15, Posterior, anterior, side, ventral, and dorsal views, ×1, hypotype USNM 154850a. [Road Canyon Formation, USNM 721s.]

16–20, Posterior, ventral, side, dorsal, and anterior views of a rotund specimen, ×1, hypotype USNM 154849. [Cathedral Mountain Formation, USNM 702a.]

21–25, Dorsal, posterior, anterior, ventral, and side views, ×1, hypotype USNM 154852a; 26–30, ventral, posterior, side, anterior, and dorsal views of a large individual, ×1, hypotype USNM 154852b; 39–41, interior, laterally tilted, and posteriorly tilted views of a brachial valve, ×1.5, hypotype USNM 154852c; 42, 43, laterally tilted and anterior views of the preceding brachial valve, ×3, showing the hinge plate and crura. [Road Canyon Formation, USNM 719x.]

31, Interior of a brachial valve, ×3, hypotype USNM 153835m; 32, interior of an immature brachial valve, ×3, hypotype USNM 153835n; 33, interior and posteriorly tilted views of another immature brachial valve, ×3, hypotype USNM 153835o; 34, 35, posteriorly tilted and interior views of another immature brachial valve, ×8, showing beginnings of hinge plate, hypotype USNM 153835p; 36, 37, posteriorly tilted and interior views of a brachial valve, ×3, showing the crura, hypotype USNM 154848e; 38, interior of an immature brachial valve, ×6, showing crura and hinge plate, hypotype USNM 153835r; 44, side view of a broken specimen, ×1.5, hypotype USNM 154848a; 45, 46, posterior, and posteriorly tilted views of the beak of the pedicle valve, ×4, showing the conjunct deltidial plates, hypotype USNM 154848b; 47, 48, interior and posteriorly tilted views of a brachial valve, ×1.5, showing hinge plate and crura, hypotype USNM 154848c; 49, interior view of the preceding brachial valve, ×4.5, showing elements of the hinge plate and the minutely crenulated socket. [Road Canyon Formation, USNM 702c.]

Anteridocus swallovianus (Shumard): 50, 51, Ventral, posterior, side, anterior, and dorsal views, ×1, showing flattened brachial valve umbo, hypotypes USNM 154855a, b (for enlarged views see Plate 538: figures 1–3); 62, 63, anterior and tilted views of the interior, ×3, showing the crura, hypotype USNM 154855d; 64, broken specimen, ×4, showing hinge plate and crura, hypotype USNM 154855c. [Bell Canyon Formation (Hegler Member), USNM 731.]

52, Ventral, posterior, side, anterior, and dorsal views, ×1, hypotype USNM 154856. [Capitan Formation, AMNH 840.]

53, Ventral, posterior, side, anterior, and dorsal views, ×1, hypotype USNM 154929 (for enlarged view see Plate 538: figures 4–6). [Bell Canyon Formation (Pinery Member), USNM 725h.]

54, Ventral, posterior, side, anterior, and dorsal views, ×1, hypotype USNM 154859d. [Capitan Formation, USNM 740.]

55, Ventral, posterior, side, anterior, and dorsal views, ×1, hypotype USNM 154857. [Capitan Formation, USNM 725-1.]

56–58, Anterior, side, and dorsal views, ×1, hypotype USNM 154858. [Capitan Formation, USNM 750a.]

59–61, Ventral, posteriorly tilted, and laterally tilted views of a specimen, ×3, showing the long crura and hinge plate, hypotype USNM 154860b. [Bell Canyon Formation (Pinery Member), USNM 725n.]

PLATE 534.—Pontisia and Anteridocus.

PLATE 535

Anteridocus, Antronaria, and Pontisia

Anteridocus paucicostatus, new species: 1, Ventral, posterior, side, anterior, and dorsal views, ×1, paratype USNM 148590a; 2–5, ventral, posterior, side, anterior, and dorsal views, ×1, and side, anterior, and dorsal views, ×2, paratype USNM 148590b; 6, interior of the brachial valve, ×4, paratype USNM 148590e. [Skinner Ranch Formation (Sullivan Peak Member), USNM 714y.]

Antronaria pluricosta, new species: 7–11, Posterior, anterior, side, dorsal, and ventral views, ×1, paratype USNM 152854c; 12–16, ventral, side, dorsal, posterior, and anterior views, ×1, paratype USNM 152854b; 17–21, posterior, anterior, side, dorsal, and ventral views, ×1, holotype USNM 152854d; 22, anterior view of the interior, ×2, showing the cardinalia, paratype USNM 152854i; 23–25, posteriorly tilted, interior, and laterally tilted views, ×2, showing median ridge, muscle field, and hinge plate, paratype USNM 152854k. [Bone Spring Formation, AMNH 591.]

Anteridocus seminudus, new species: 26, 27, Ventral, posterior, side, anterior, and dorsal views, ×1, paratypes USNM 152855f, g; 28–31, ventral, posterior, side, anterior, and dorsal views, ×1, and side, anterior, and dorsal views, ×3, holotype USNM 152855h; 32, 33, ventral view of the interior, ×2, ×6, showing the crura and hinge plate, paratype USNM 154864a; 34, 35, interior of the pedicle valve, ×2, ×4, showing incipient deltidial plates, paratype USNM 154864b; 36–38, interior, laterally tilted, and posteriorly tilted views of another brachial valve, ×6, showing hinge plate, crura, and lack of a median septum, paratype USNM 154864c. [Road Canyon Formation, USNM 722f.]

39–42, Ventral, posterior, side, anterior, and dorsal views, ×1, and dorsal, anterior, and side views, ×2, paratype USNM 154863a; 43–46, ventral, posterior, side, anterior, and dorsal views, ×1, and anterior, dorsal, and side views, ×2, paratype USNM 154863b; 47, ventral, posterior, side, anterior, and dorsal views, ×1, paratype USNM 154863c; 48, 49, posteriorly tilted and interior views of the brachial valve, ×6, lacking a median septum, paratype USNM 154863d; 50, 51, posteriorly tilted view, ×2, ×4, showing the dental plates and incipient deltidial plates, paratype USNM 154863e. [Road Canyon Formation, USNM 721x.]

Pontisia stehlii tumidosa, new subspecies: 52–56, Side, posterior, anterior, dorsal, and ventral views, ×1, holotype USNM 148623h; 57–61, posterior, anterior, side, ventral, and dorsal views of a complete specimen, ×1, paratype USNM 148623g; 62, 63, ventral, posterior, side, anterior and dorsal views, ×1, of two small paratypes, USNM 148623b, c; 64, 65, interior and posteriorly tilted views of the brachial valve, ×3, showing the cardinalia, paratype USNM 154682a; 66, anterolateral view of the interior, ×3, showing the crura paratype USNM 154682b. [Road Canyon Formation, USNM 702c.]

PLATE 535.—Anteridocus, Antronaria, and Pontisia.

PLATE 536

Antronaria and Pontisia

Antronaria transversa (R. E. King): 1–5, Posterior, anterior, side, ventral, and dorsal views, ×1, hypotype USNM 148645e; 6–9, dorsal, side, anterior, and ventral views of an immature individual, ×1, hypotype USNM 148645a. [Hess Formation (Taylor Ranch Member), USNM 702d.]

10–14, Anterior, posterior, side, ventral, and dorsal views, ×1, hypotype USNM 148651a; 25, 26, specimen with beak broken away to show cardinalia, ×1, ×3, hypotype USNM 154865a; 27, posterior of another brachial valve, ×3, showing crura, hypotype USNM 154865b. [Hess Formation (Taylor Ranch Member), USNM 702e.]

15–19, Anterior, dorsal, side, posterior, and ventral views of a large specimen, ×1, hypotype USNM 154932. [Hess Formation (Taylor Ranch Member), USNM 716o.]

20–24, Ventral, anterior, dorsal, posterior, and side views of another large individual, ×1, hypotype USNM 148668a. [Hess Formation (Taylor Ranch Member), USNM 716n.]

Pontisia ventricola, new species: 28, Dorsal view of an immature specimen, ×1, paratype USNM 152860b; 29–31, ventral, posterior, side, anterior and dorsal views, ×1, young paratypes USNM 152860d, h, j; 32–34, ventral, posterior, side, anterior, and dorsal views, ×1, and side and dorsal views, ×2, paratype USNM 152860k; 35, posterior of the preceding specimen, ×4, showing conjunct deltidial plates; 36, 37, ventral, posterior, side, anterior, and dorsal views, ×1, holotype USNM 152860m (for enlarged views see plate 520: figures 51–53) and paratype USNM 152860s; 38, anterolateral view of the interior, ×3, showing the crura, paratype USNM 154866a; 39, 40, interior and posteriorly tilted view of the pedicle valve, ×1.5, showing the dental plates, paratype USNM 154866b; 41, 42, posteriorly tilted and interior views of the preceding pedicle valve, ×3, showing dental plates and disjunct deltidial plates; 43, 44, interior and posteriorly tilted views of the brachial valve, ×3, showing absence of median septum, the hinge plate, and crura, paratype USNM 154866c; 45–48, interior, ×1.5, and anterior, interior, and laterally tilted views, ×3, of a brachial valve, showing cardinalia, paratype USNM 154866d; 49, posterior of the preceding specimen, ×4, showing the hinge plate; 50, 51, interior of another specimen showing hinge plate and crura and absence of median septum, ×4, paratype USNM 154866e. [Hess Formation (top), USNM 726n.]

PLATE 536.—Antronaria and Pontisia.

PLATE 537

Antronaria

Antronaria voluminosa, new species: 1, 2, Ventral, anterior, side, and dorsal views, ×1, immature paratypes USNM 148736b, d; 3–7, dorsal, ventral, side, anterior, and posterior views, ×1, of a young paratype USNM 148736f; 8–12, dorsal, ventral, side, anterior, and posterior views of a specimen more mature than the preceding, ×1, paratype USNM 148736g; 13–17, dorsal, ventral, side, anterior, and posterior views of a young adult, ×1, paratype USNM 148736i; 18–22, posterior, anterior, side, ventral, and dorsal views of a very large individual, ×1, holotype USNM 148736-1; 28–32, posterior, side, anterior, dorsal, and ventral views of a complete specimen, ×1, paratype USNM 154868a; 33–37, ventral, posterior, side, anterior, and dorsal views of a large specimen, ×1, paratype USNM 154868b. [Skinner Ranch Formation (Poplar Tank Member), USNM 708e.]

23–27, posterior, dorsal, side, ventral, and anterior views of a complete specimen, ×1, paratype USNM 148742. [Skinner Ranch Formation (Decie Ranch Member), USNM 707a.]

38, Anterolateral view of the interior, ×2, showing crura, paratype USNM 154869a; 39, interior of the pedicle valve, ×1, paratype USNM 154869b; 40, anterior view of the interior, ×2, showing short median ridge and crus, paratype USNM 154869c; 41–43, interior, posteriorly tilted, and side views of a brachial valve, ×1, showing crura and hinge plate, paratype USNM 154870; 44–46, same views as the preceding, ×2, showing greater detail; 47, interior of the pedicle valve of the preceding specimen, ×2, showing dental plates and muscle field; 48, 49, interior and laterally tilted views of a brachial valve, ×1, showing hinge plate and crura, paratype USNM 154869d; 50, 51, same views as preceding, ×2. [Skinner Ranch Formation (Sullivan Peak Member), USNM 707-1.]

PLATE 537.—Antronaria.

PLATE 538

Anteridocus and Antronaria

Anteridocus swallovianus (Shumard): 1–3, Dorsal, anterior, and side views of a complete specimen, ×2, showing flattened dorsal umbo, hypotype USNM 154855b (for natural size views, see Plate 534: figures 50–51). [Bell Canyon Formation (Hegler Member), USNM 731.]

4–6, Side, anterior, and dorsal views of another complete specimen, ×2, hypotype USNM 154859d (for natural size views see Plate 534: figure 54); 7, posterior of the preceding specimen, ×4, showing the conjunct deltidial plates. [Bell Canyon Formation (Pinery Member), USNM 725h.]

8, Interior of the brachial valve, ×4, hypotype USNM 154861a. [Bell Canyon Formation (Lamar Member), USNM 738.]

9, 10, Posteriorly tilted and interior views of the pedicle valve, ×1.5, showing a trace of pallial marks, hypotype USNM 154860a; 11, side view, showing the crura, ×3, hypotype USNM 154860d. [Bell Canyon Formation (Pinery Member), USNM 725n.]

Antronaria titania, new species: 12–16, Anterior, posterior, side, ventral, and dorsal views of a complete specimen, ×1, paratype USNM 154873. [Skinner Ranch Formation (base), USNM 720e.]

17–21, Ventral, side, dorsal, posterior, and anterior views of a complete specimen, ×1, paratype USNM 154874. [Skinner Ranch Formation (Decie Ranch Member), USNM 727u.]

22–26, Ventral, dorsal, side, posterior, and anterior views of a large specimen, ×1, paratype USNM 154872a; 37, interior of the brachial valve, ×2, paratype USNM 154872b. [Skinner Ranch Formation (base), USNM 705a.]

27–31, Side, ventral, anterior, posterior, and dorsal views of a large complete specimen, ×1, paratype USNM 154871; 32–36, posterior, anterior, side, ventral, and dorsal views of a large adult, ×1, holotype USNM 148660j. [Skinner Ranch Formation (Decie Ranch Member), USNM 707a.]

Antronaria transversa (R. E. King): 38–42, Ventral, anterior, side, posterior, and dorsal views, of a young specimen, ×1, paratype YPM 12519. [Hess Formation (Taylor Ranch Member), R. E. King 212.]

43–47, Dorsal, anterior, ventral, posterior, and side views, ×1, of another paratype YPM 10674. [Hess Formation (Taylor Ranch Member), R. E. King locality 107.]

48–52, Posterior, dorsal, anterior, side, and ventral views, ×1, holotype YPM 12518. [Hess Formation (Taylor Ranch Member), R. E. King 222.]

Anteridocus gongylus, new species: 53, Anterior view, ×6, showing the hinge plate and crura, paratype USNM 154875a; 54, dorsal view of the interior, ×6, showing under side of hinge plate and crura, paratype USNM 154875b; 55, ventral view of another specimen, ×6, showing the crura, paratype USNM 154875c; 56, ventral view of the interior, ×4, showing cardinalia, paratype USNM 154875d; 57, interior of a brachial valve, ×6, showing hinge plate and crura, paratype USNM 154875e; 58, interior of another brachial valve, ×4, showing hinge plate and crura, paratype USNM 154875f (for additional and exterior views of this species see plate 539). [Cathedral Mountain Formation, USNM 702a.]

PLATE 538.—Anteridocus and Antronaria.

PLATE 539

Hemileurus and Anteridocus

Hemileurus runcinatus, new species: 1, 2, Ventral, posterior, side, anterior, and dorsal views, ×1, young paratypes USNM 148071i, g; 3, ventral, posterior, side, anterior, and dorsal views of an adult, ×1, holotype USNM 148071h; 4, broken specimen, ×4, showing crura and absence of inner hinge plates, paratype USNM 14807-1; 5, another broken specimen, ×4, showing the same features as the preceding, paratype USNM 148071k; 6, ventral view, ×4, showing the crura, paratype USNM 148071j. [Neal Ranch Formation (beds 12–14 of P. B. King), USNM 701k.]

7, 8, Ventral, posterior, side, anterior, and dorsal views, ×1, of two paratypes USNM 154876a, c. [Neal Ranch Formation (beds 12–14 of P. B. King), USNM 701h.]

Anteridocus erugatus, new species: 9, Dorsal view of a complete but immature specimen, ×2, paratype USNM 154877a; 10, ventral, posterior, side, anterior, and dorsal views, ×1, paratype USNM 154878a; 11–14, ventral, posterior, side, anterior, and dorsal views, ×1, and dorsal, anterior, and side views, ×2, holotype USNM 154878b; 15–18, ventral, posterior, side, anterior, and dorsal views, ×1, and anterior, dorsal, and side views, ×2, paratype USNM 154878c; 23–25, posteriorly tilted and interior views, ×2, and posterior, ×6, showing dental plates and incipient deltidial plates, paratype USNM 154877b; 26, 27, dorsal view of the interior, ×2, ×6, showing underside of hinge plate and crura, paratype USNM 154877c; 28–30, interior view, ×2, and laterally tilted and posterior views, ×6, of the brachial valve, showing the long, curved crura and slight development of inner hinge plates, paratype USNM 154877d; 31, 32, dorsal view of the interior, ×2, ×6, showing underside of crura, paratype USNM 154877e; 33, posterior part of the brachial valve with part of pedicle valve attached, ×8, showing cardinalia, dental plates, and a fused hinge plate, paratype USNM 154877f; 34, 35, interior view of the brachial valve, ×2, ×6, showing strongly developed and nearly coalesced inner hinge plates, paratype USNM 154877g; 36, interior of another brachial valve with beak of pedicle valve attached, ×6, showing dental plates and coalesced inner hinge plates, paratype USNM 154877h; 37–39, interior view, ×2, and interior and laterally tilted views, ×6, of a brachial valve with fused hinge plate and stout crura, paratype USNM 154877i. [Road Canyon Formation, USNM 702c.]

19–22, Posterior, anterior, side, ventral, and dorsal views, ×1, and side, anterior, and dorsal views, ×2, of a complete specimen, paratype USNM 148123a. [Cathedral Mountain Formation, USNM 708.]

Anteridocus gongylus, new species: 40, Ventral, posterior, side, anterior, and dorsal views, ×1, paratype USNM 154879a; 41–44, ventral, posterior, side, anterior, and dorsal views, ×1, and dorsal, anterior, and side views, ×2, of another paratype USNM 154879b. [Cathedral Mountain Formation, USNM 708.]

45, Dorsal view of an immature, complete specimen, ×1, paratype USNM 154875i; 46, ventral, posterior, side, anterior, and dorsal view of another immature specimen, ×1, paratype USNM 154875j; 47–50, ventral, posterior, side, anterior, and dorsal views, ×1, and dorsal, anterior, and side views, ×2, of a complete specimen, paratype USNM 154875-1; 51–54, ventral, posterior, side, anterior, and dorsal views, ×1, and dorsal, side, and anterior views, ×2, of another paratype USNM 154875k; 55, ventral, posterior, side, anterior and dorsal views, ×1, of a complete specimen, paratype USNM 148105f; 56–59, ventral, posterior, side, anterior and dorsal views, ×1, and side, anterior and dorsal views, ×2, of another paratype USNM 148105g. [Cathedral Mountain Formation, USNM 702a.]

PLATE 539.—Hemileurus and Anteridocus.

PLATE 540

Anteridocus, Allorhynchus, and Petasmatherus

Anteridocus eximius, new species: 1, 2, Ventral, posterior, side, anterior, and dorsal views, ×1, of paratype USNM 154880f and holotype USNM 154880d; 3, interior of the brachial valve, ×3, paratype USNM 154880g. [Bone Spring Formation (Cutoff Member), AMNH 678.]

Allorhynchus formulosum, new species: 4–8, Ventral, posterior, side, anterior, and dorsal views, ×1, and anterior, posterior, dorsal, and side views, ×2, holotype USNM 154881a; 9, ventral, posterior, side, anterior, and dorsal views of an adult, ×1, paratype USNM 154882h; 10–12, anterior, side, and dorsal views, ×2, of another paratype USNM 154882g; 13, interior of the brachial valve, ×3, paratype USNM 154881c; 14, interior of the pedicle valve, ×3, showing incipient deltidial plates, paratype USNM 154881d. [Cherry Canyon Formation (Getaway Member), AMNH 585.]

Petasmatherus mundus, new species: 15, Ventral, posterior, side, anterior, and dorsal views, ×1, paratype USNM 153472c; 16–21, ventral, posterior, side, anterior, and dorsal views, ×1, and posterior, anterior, side, dorsal, and ventral views, ×3, holotype USNM 153472a; 22, interior of the brachial valve, ×3, paratype USNM 153472d; 23–25, laterally tilted, interior, and posteriorly tilted views, ×9, showing the divided hinge plate, of the preceding specimen. [Cathedral Mountain Formation, USNM 702–low.]

Petasmatherus nitidus, new species: 26–30, Ventral, posterior, side, anterior, and dorsal views, ×1, and posterior, side, dorsal, and anterior views, ×3, paratype USNM 154883a; 31, 32, ventral, posterior, side, anterior, and dorsal views, ×1, paratypes USNM 154883b, j; 49, broken specimen, showing the divided hinge plate, ×4, paratype USNM 154883k. [Road Canyon Formation, USNM 721x.]

33, 34, 40, ventral, posterior, side, anterior, and dorsal views of two immature and one adult specimen, ×1, paratypes USNM 154884a, b, g; 35–39, ventral, posterior, side, anterior, and dorsal views, ×1, and anterior, posterior, dorsal, and side views, ×3, holotype USNM 154884h; 51, 52, interior and laterally tilted views, ×6, showing divided hinge plate, median ridge, and crura, paratype USNM 154884c; 53, interior of another brachial valve, ×6, paratype USNM 154884d; 54, ventral view of the interior, ×6, paratype USNM 154884f; 55, posterior of pedicle valve, showing disjunct deltidial plates, ×6, paratype USNM 154884e. [Road Canyon Formation, USNM 721j.]

41–45, Posterior, anterior, side, ventral, and dorsal views, ×1, and dorsal, side, posterior, and anterior views, ×3, paratype USNM 154885a; 46, 47, posteriorly tilted and interior views, ×2, of the pedicle valve, paratype USNM 154885b; 48, posteriorly tilted view of the preceding pedicle valve, ×3, showing dental plates and disjunct deltidial plates; 50, interior of a brachial valve, ×2, paratype USNM 154855c. [Road Canyon Formation, USNM 721z.]

PLATE 540.—Anteridocus, Allorhynchus, and Petasmatherus.

PLATE 541

Allorhynchus, Petasmatherus, and Phrenophoria

Allorhynchus permianum permianum Stehli: 1–5, Posterior, anterior, side, ventral, and dorsal views, ×1, hypotype USNM 148054a; 6–10, posterior, anterior, side, ventral, and dorsal views, ×1, hypotype USNM 148054b; 11–15, ventral, posterior, side, dorsal, and anterior views of a young adult, ×1, hypotype USNM 148054c; 16–20, ventral, dorsal, side, posterior, and anterior views of another young adult, ×1, hypotype USNM 1148054d; 21, 22, posteriorly tilted and interior views of the pedicle valve, ×1.5, showing dental and disjunct deltidial plates, hypotype USNM 148054e; 23, interior of a brachial valve, ×1.5, showing divided hinge plate, hypotype USNM 148054f; 24, 25, posteriorly tilted and interior views of the preceding specimen, ×4.5, showing inner hinge plates, crura, and threadlike median ridge; 26, broken specimen, ×1.5, showing cardinalia, hypotype USNM 148054g; 27, interior of another brachial valve, ×1.5, hypotype USNM 148054h; 28, 29, laterally tilted and posteriorly tilted views of the preceding specimen, ×3, showing cardinalia; 30, interior of the preceding specimen, ×4.5, showing cardinalia. [Cherry Canyon Formation (Getaway Member), USNM 728.]

Petasmatherus pumilus, new species: 31–35, Side, anterior, ventral, and dorsal views, ×1, and ventral, anterior, posterior and side views, ×2, paratype USNM 148063a. [Road Canyon Formation, USNM 706f.]

36–40, Posterior, anterior, side, ventral, and dorsal views, ×1, and dorsal, anterior, side, and posterior views, ×3, paratype USNM 154886. [Road Canyon Formation, USNM 721j.]

41, Ventral, posterior, side, anterior, and dorsal views, ×1, paratype USNM 148061d; 42–46, ventral, posterior, side, anterior, and dorsal views, ×1, and posterior, dorsal, anterior, and side views, ×2, paratype USNM 148061g; 47–51, ventral, posterior, side, anterior, and dorsal views, ×1, and side, posterior, anterior, and dorsal views, ×2, of a bored specimen, holotype USNM 148061e; 52, dorsal views of two immature individuals, ×1, paratypes USNM 148061h, i; 53, interior of the pedicle valve, ×6, showing disjunct deltidial plates, paratype USNM 148061j; 54, 55, interior and laterally tilted views of a brachial valve, ×6, showing divided hinge plate, paratype USNM 148061k; 56, interior of another brachial valve, ×6, showing divided hinge plate, paratype USNM 148061-1. [Road Canyon Formation, USNM 707e.]

Petasmatherus cf. P. pumilus, new species: 57, 58, Ventral, posterior, side, anterior, and dorsal views, ×2, and dorsal views, ×1, figured specimens USNM 154887b, a. [Cibolo Formation (Thin-bedded Zone of Udden), USNM 738-1.]

Phrenophoria vetula, new species: 59, Dorsal view of a complete specimen, ×1, paratype USNM 154888; 60, 61, exterior and interior of the brachial valve of the preceding specimen, ×2; 62, 63, interior and exterior of the pedicle valve of the preceding specimen, ×2. [Cathedral Mountain Formation, USNM 721u.]

PLATE 541.—Allorhynchus, Petasmatherus, and Phrenophoria.

PLATE 542

Allorhynchus

Allorhynchus permianum wordense, new subspecies: 1, Dorsal view of two immature specimens, ×1, paratypes USNM 154889a, b; 2, 3, ventral, posterior, side, anterior, and dorsal views, ×1, of two young individuals, paratypes USNM 148084e, f; 4–8, posterior, anterior, side, ventral, and dorsal views, ×1, of a large adult, paratype USNM 148084g; 9–13, ventral, dorsal, side, posterior, and anterior views, ×1, of a complete specimen, holotype USNM 154889c; 36–38, interior and posteriorly tilted views, ×1.5, and interior view, ×3, of the pedicle valve, showing disjunct deltidial plates, paratype USNM 154889d; 39, 40, dorsal view of another interior, ×1.5, ×3, showing underside of crura, paratype USNM 154889e; 41–43, interior, laterally tilted, and posteriorly tilted views of a brachial valve, ×1.5, showing the divided hinge plate, paratype USNM 154889f; 44, posterior of the preceding specimen, ×3, showing the divided hinge plate; 47, anterolateral view of another interior, ×4, showing the crura, paratype USNM 154889h. [Word Formation (Willis Ranch Member), USNM 706.]

14–18, Posterior, side, anterior, ventral, and dorsal views of a young adult, ×1, paratype USNM 154890a; 19–23, ventral, dorsal, side, posterior, and anterior views of an immature specimen, ×1, paratype USNM 154890b; 48, ventral view of a broken specimen, ×3, showing the cardinalia, paratype USNM 154890c; 49, interior of the brachial valve, ×3, showing the divided hinge plate and also small inner hinge plates, paratype USNM 154890d. [Word Formation (lens between the Willis Ranch and Appel Ranch members), USNM 706b.]

24–28, Ventral, posterior, side, anterior, and dorsal views of an average adult, ×1, paratype USNM 148081a; 29–33, posterior, side, anterior, ventral, and dorsal views of a young adult, ×1, paratype USNM 148081b; 34, 35, dorsal, anterior, and side views of two immature specimens, ×1, paratypes USNM 148081c, d; 45, 46, interior of the brachial valve, ×1.5, ×3, showing divided hinge plate and inner hinge plates, paratype USNM 148081e; 50, 51, interior, ×1, and posterior, ×3, of the pedicle valve showing disjunct deltidial plates, paratype USNM 148081e (counterparts of the same specimen). [Word Formation (Willis Ranch Member), USNM 706e.]

Allorhynchus triangulatum, new species: 52–54, Ventral, posterior, side, anterior, and dorsal views, ×1, paratypes USNM 148092d, e, c; 55, ventral, posterior, side, anterior, and dorsal views of the holotype, ×1, USNM 148092b; 56, interior of the pedicle valve, ×3, showing disjunct deltidial plates, paratype USNM 148092h; 57, 58, interior and posteriorly tilted views of the brachial valve, ×1.5, paratype USNM 148092i; 59, 60, same views as preceding, ca.X5, showing divided hinge plate. [Word Formation (China Tank Member), USNM 706c.]

Allorhynchus venustulum, new species: 61, 62, Ventral, posterior, side, anterior, and dorsal views, ×2, and dorsal view, ×1, paratype USNM 154891a and paratype USNM 154891b; 63, interior of the pedicle valve, ×4, showing teeth and disjunct deltidial plates, paratype USNM 154891c; 64, interior of the brachial valve, ×6, showing divided hinge plate, well-developed inner hinge plates, and pallial marks, paratype USNM 154891d. [Bell Canyon Formation (Lamar Member), USNM 728p.]

PLATE 542.—Allorhynchus.

PLATE 543

Allorhynchus and Cenorhynchia

Allorhynchus variabile, new species: 1, 2, Ventral, posterior, side, anterior, and dorsal views, ×1, paratypes USNM 154892b, a. [Word Formation (Willis Ranch Member), USNM 706.]

3, Dorsal, anterior, and side views, ×1, of two immature paratypes USNM 148090e, f; 4–6 ventral, posterior, side, anterior, and dorsal views, ×1, of three adult paratypes USNM 148090d, c, b; 7, ventral, posterior, side, anterior, and dorsal views, ×1, of the holotype USNM 148090a; 8, 9, posteriorly tilted and interior views of the brachial valve, ×1.5, paratype USNM 148090g; 10, 11, same views, ×3, showing the divided hinge plate with its inner hinge plates; 12, 13, interior view, ×1.5, and posteriorly tilted view, ×3, of the pedicle valve, showing disjunct deltidial plates, paratype USNM 148090h. [Word Formation (China Tank Member), USNM 706c.]

Allorhynchus venustulum, new species: 14, Ventral, posterior, side, anterior, and dorsal views, ×1, paratype USNM 152804f; 15–19, ventral, posterior, side, anterior, and dorsal views, ×1, and side, posterior, anterior, and dorsal views, ×3, holotype USNM 152804g. [Bell Canyon Formation (Lamar Member), USNM 738b.]

20, Ventral, posterior, side, anterior, and dorsal views, ×1, paratype USNM 154893a; 27, broken specimen, ×6, showing the divided hinge plate, paratype USNM 154893b; 28, laterally tilted view of the brachial valve, ×2, paratype 154893c; 29, 30, posteriorly tilted and interior views of the preceding specimen, ×6, showing cardinalia; 31, 32, interior and posteriorly tilted views of the pedicle valve, ×2, showing dental plates, paratype USNM 154893d; 33, interior of the preceding specimen, ×4, showing disjunct deltidial plates. [Bell Canyon Formation (Lamar Member), USNM 738.]

21–25, Ventral, posterior, anterior, and dorsal views, ×1, and side, dorsal, anterior and posterior views, ×3, paratype USNM 154894. [Bell Canyon Formation (Lamar Member), AMNH 40.]

26, Ventral, posterior, side, anterior, and dorsal views, ×1, paratype USNM 154895. [Bell Canyon Formation (Lamar Member), USNM 728r.]

Cenorhynchia atmeta, new species: 34–37, Posterior, anterior, side, ventral, and dorsal views, ×2, and dorsal, side, and anterior views, ×4, paratype USNM 154896. [Road Canyon Formation, USNM 721o.]

38–41, Posterior, side, anterior, and dorsal views, ×2, and dorsal view, ×1, and anterior, side, and dorsal views, ×4, holotype USNM 148162d; 42, posterior, side, anterior, and dorsal views, ×2, and dorsal view, ×1, paratype USNM 148162e; 47, posterior of pedicle valve, showing tooth and lack of deltidial plates, ×10, paratype USNM 148162f; 48, interior of the brachial valve, showing hinge plate, ×10, paratype USNM 148162h. [Road Canyon Formation, USNM 710u.]

43–46, Posterior, dorsal, ×1, and anterior, ventral, side, and dorsal views, ×2, and side, anterior, and dorsal views, ×4, paratype USNM 154897a. [Road Canyon Formation (base), USNM 702c.]

49, 50, Ventral, posterior, side, anterior, and dorsal views, ×2, paratypes USNM 154898a, b. [Road Canyon Formation, USNM 724j.]

PLATE 543.—Allorhynchus and Cenorhynchia.

PLATE 544

Cenorhynchia and Tautosia

Cenorhynchia fracida, new species: 1, Dorsal, posterior, side, anterior, and posterior views, ×1, paratype USNM 148167b; 2–5, ventral, posterior, side, anterior, and dorsal views, ×1, and side, dorsal, and anterior views, ×2, paratype USNM 148167d; 6–9, ventral, posterior, side, anterior, and dorsal views, ×1, and anterior, side, and dorsal views, ×2, holotype USNM 148167a; 10, 11, interior view, ×1.5, and interior tilted posteriorly, ×3, showing dental plates and disjunct deltidial plates, paratype USNM 148168b; 12, ventral view of a broken specimen, ×4, showing the hinge plate not quite coalesced and the long crura, paratype USNM 148168a; 13–15, laterally tilted, interior, and posteriorly tilted views of the brachial valve, ×4, showing fused hinge plate and median septum, paratype USNM 148168c; 16, 17, interior and posteriorly tilted views of the preceding brachial valve, ×1.5; 18–20, interior, laterally tilted, and anterior view, ×4, of another brachial valve younger than the preceding with hinge plate not yet coalesced, paratype USNM 148168f; 21, interior of a young brachial valve, showing the fused hinge plate and long crura, ×6, paratype USNM 148168g. [Word Formation (lens between Willis Ranch and Appel Ranch members), USNM 706b.]

Cenorhynchia hebata, new species: 22–25, Ventral, posterior, side, anterior, and dorsal views, ×1, and anterior, side, and dorsal views, ×3, paratype USNM 148185b; 26–29, ventral, posterior, side, anterior, and dorsal views, ×1, and dorsal, anterior, and side views, ×3, holotype USNM 148185a; 30, 31, interior and posteriorly tilted views of a pedicle valve, ×4, showing neither dental nor deltidial plates, paratype USNM 148185g; 32–34, interior, ×1.5, of the brachial valve, and interior, and posteriorly tilted views, ×5, of the same specimen, showing the hinge plate, paratype USNM 148185g; 35, 36, interior of brachial valve, ×2, ×6, showing hinge plate, paratype USNM 148185f; 37–40, interior posteriorly tilted view, ×2, and posteriorly tilted, interior and laterally tilted views, ×6, of a brachial valve, showing hinge plate and median septum, paratype USNM 148185e. [Neal Ranch Formation (beds 12–14 of P. B. King), USNM 701k.]

Tautosia distorta, new species: 41–45, Dorsal, anterior, posterior, side, and ventral views, ×1, of an angular specimen, holotype USNM 153488a; 46, dorsal view of the preceding specimen, ×2; 47, interior of the pedicle valve, ×2, showing dental plates, paratype USNM 153488b. [Word Formation (Appel Ranch Member), USNM 727j.]

PLATE 544.—Cenorhynchia and Tautosia.

PLATE 545

Cenorhynchia

Cenorhynchia mitigata, new species: 1, Ventral, posterior, side, anterior, and dorsal views, ×1, paratype USNM 148193e; 2–5, ventral, posterior, side, anterior, and dorsal views, ×1, and anterior, dorsal, and side views, ×2, paratype USNM 148193f; 6–9, ventral, posterior, side, anterior, and dorsal views, ×1, and dorsal, side, and anterior views, ×2, holotype USNM 148193h; 20, anterior view, ×4, showing the median septum and crura, paratype USNM 154901a; 21, interior of the pedicle valve tilted posteriorly to show the dental plates, ×3, paratype USNM 154901b; 22, 23, posteriorly tilted and interior views of the brachial valve counterpart of the preceding, ×4, showing a divided hinge plate and crura; 24, interior of preceding, ×1.5. [Cathedral Mountain Formation, USNM 702a.]

10–13, Ventral, posterior, side, anterior, and dorsal views, ×1, and side, dorsal, and anterior views, ×2, paratype USNM 148205a. [Cathedral Mountain Formation, USNM 702–low.]

14, Ventral, posterior, side, anterior, and dorsal views, ×1, paratype USNM 154900; 25, posteriorly tilted view of the pedicle valve of the preceding specimen, ×3, showing dental plates but no deltidial plates; 26, posteriorly tilted brachial valve interior of the preceding specimen, ×1.5; 27, 28, interior and posteriorly tilted views of the preceding brachial valve, ×6, showing cardinalia and median septum. [Road Canyon Formation, USNM 721o.]

15–19, Ventral, posterior, side, anterior, and dorsal views, ×1, and side, anterior, and dorsal views, ×2, paratype USNM 154899. [Road Canyon Formation, USNM 719x.]

Cenorhynchia parvula, new species: 29, Ventral, posterior, side, anterior, and dorsal views, ×1, paratype USNM 148189f; 30–33, ventral, posterior, side, anterior, and dorsal views, ×1, and side, dorsal, and anterior views, ×3, holotype USNM 148189g; 34–36, interior view, ×2, and interior and posteriorly tilted views, ×6, showing hinge plate and crura, paratype USNM 148189h. [Road Canyon Formation, USNM 703a.]

37, Ventral, posterior, side, anterior, and dorsal views, ×1, paratype USNM 154902b; 38–41, ventral, posterior, side, anterior, and dorsal views, ×1, and anterior, side, and dorsal views, ×2, paratype USNM 154902a. [Road Canyon Formation, USNM 702c.]

Cenorhynchia nasuta, new species: 42–45, Posterior, anterior, side, ventral, and dorsal views, ×1, and dorsal, side, and anterior views, ×2, paratype USNM 154903a; 49, 50, interior view of the brachial valve, ×1.5, ×4.5, showing undivided hinge plate and strong median septum, paratype USNM 154903b. [Cherry Canyon Formation (Getaway Member), AMNH 585.]

46, 47, Ventral, posterior, side, anterior, and dorsal views, ×1, paratype USNM 152813a and holotype USNM 152813c; 48, ventral and tilted views of the holotype, ×4, with beak removed to show cardinalia; 51, interior of the pedicle valve with a mere trace of deltidial plate, ×3, paratype USNM 152813d. [Cherry Canyon Formation (Getaway Member), AMNH 512.]

PLATE 545.—Cenorhynchia.

PLATE 546

Cenorhynchia and Bryorhynchus

Cenorhynchia saginata, new species: 1, 2, Dorsal, anterior, side, posterior, and ventral views, ×1, paratypes USNM 148174a, b; 3–5, dorsal, side, and anterior views, ×2, of the latter paratype. [Road Canyon Formation, USNM 707e.]

6–8, 13, Ventral, posterior, side, anterior, and dorsal views, ×1, of paratypes USNM 148212g, h, i, k; 9–12, ventral, posterior, side, anterior, and dorsal views, ×1, and anterior, dorsal, and side views, ×2, holotype USNM l48212j; 19, ventral view of the interior, ×4, showing underside of crura, paratype USNM 148212m; 20, interior of a brachial valve, ×1.5, paratype USNM 148212n; 21–24, posteriorly tilted, interior, anterior, and side views of the preceding brachial valve, ×5, showing the divided hinge plate and small, narrow inner hinge plates. [Road Canyon Formation (base), USNM 702c.]

14, Dorsal, anterior, side, posterior, and ventral views, ×1, paratype USNM 154904. [Road Canyon Formation, USNM 719x.]

15–18, Ventral, anterior, side, posterior, and dorsal views, ×1, and dorsal, side, and anterior views, ×2, paratype USNM 148176. [Road Canyon Formation, USNM 703d.]

Bryorhynchus bisulcatum (Shumard): 25, Interior of the pedicle valve, ×2, showing the muscle scars, hypotype USNM 154909h. [Bell Canyon Formation (Hegler Member), USNM 731.]

Cenorhynchia triangulata, new species: 26–29, Ventral, posterior, side, anterior, and dorsal views, ×1, and dorsal, anterior, and side views, ×2, paratype USNM 148165a; 30–33, ventral, posterior, side, anterior, and dorsal views, ×1, and anterior, dorsal, and side views, ×2, holotype USNM 148165b; 34, 35, anterior and interior views of the brachial valve, ×1.5, paratype USNM 148165d; 36, 37, interior and laterally tilted views of the preceding specimen, ×5, showing the cardinalia and septum; 38, interior of the pedicle valve, ×1.5, paratype USNM 148165e; 39, anterolateral view of a specimen showing median septum and crura, ×6, paratype USNM 148165f. [Word Formation (Willis Ranch Member), USNM 706.]

PLATE 546.—Cenorhynchia and Bryorhynchus.

PLATE 547

Cenorhynchia and Bryorhynchus

Cenorhynchia ventricosa, new species: 1–5, Anterior, posterior, side, dorsal, and ventral views, ×1, holotype USNM 148762. [Neal Ranch Formation (bed 4), USNM 701d.]

Bryorhynchus bisulcatum (Shumard): 6–10, Posterior, anterior, side, ventral, and dorsal views of a complete specimen, ×1, hypotype USNM 154905a; 77, 78, anterior view of the cardinalia, ×1.5, ×5, showing the long slender crura, hypotype USNM 154905c. [Bell Canyon Formation (Pinery Member), USNM 725h.]

11, 12, Side, anterior, and dorsal views of two immature specimens, ×1, hypotypes USNM 154906b, a; 13–17, posterior, anterior, side, ventral, and dorsal views of a young specimen, ×1, hypotype USNM 154906c; 18–22, ventral, dorsal, side, anterior, and posterior views of a young adult, ×1, hypotype USNM 154906d; 76, anterior view, ×4, showing crura and vestigial septum, hypotype USNM 154906e. [Bell Canyon Formation (Pinery Member), AMNH 33.]

23–27, Posterior, anterior, ventral, side, and dorsal views of a full-grown adult, ×1, hypotype USNM 154907. [Bell Canyon Formation (Hegler Member), USNM 732a.]

28–32, Ventral, dorsal, side, anterior, and posterior views of a complete specimen, ×1, hypotype USNM 154908a; 33–37, posterior, side, dorsal, anterior, and ventral views of a complete specimen, ×1, hypotype USNM 154908b; 38, 39, dorsal and anterior views of a specimen with coral attached, ×1, paratype USNM 154908c; 46–50, dorsal, ventral, side, anterior, and posterior views of a large strong costellate specimen, ×1, hypotype USNM 154908d; 63, 64, interior and posteriorly tilted views of the pedicle valve, ×1.5, hypotype USNM 154908f; 70, 71, interior views of another pedicle valve, ×1, hypotype USNM 154908g; 72–75, laterally tilted and interior views, ×1, and the same views, ×2, of the brachial valve, showing the long crura, hypotype USNM 154908i. [Bell Canyon Formation (Rader Member), USNM 725f.]

40, Side view of a complete specimen with attached corals, ×1, hypotype USNM 154909a; 41–45, anterior, posterior, side, ventral, and dorsal views of a small adult, ×1, hypotype USNM 154909b; 51–55, ventral, side, dorsal, posterior, and anterior views of a specimen with few costae, ×1, hypotype USNM 154909c; 56–60, ventral, dorsal, side, anterior, and posterior views of an anteriorly costate specimen, ×1, hypotype USNM 154909d; 65–69, posteriorly tilted, interior, and laterally tilted views, ×2, and posteriorly tilted and interior views of a pedicle valve, ×1, showing the muscles and pallial marks, hypotype USNM 154909i; 79, interior of an obese pedicle valve, ×2, showing muscles and part of the pallial marks, hypotype USNM 154909j. [Bell Canyon Formation (Hegler Member), USNM 731.]

61, Dorsal view of a large complete specimen, ×1, hypotype USNM 154910a; 62, posterior of the preceding specimen, ×5, showing foramen and conjunct deltidial plates. [Bell Canyon Formation (Pinery Member), USNM 725n.]

PLATE 547.—Cenorhynchia and Bryorhynchus.

PLATE 548

Bryorhynchus, Leiorhynchoidea, and Madarosia

Bryorhynchus gratiosum (Girty): 1–5, Posterior, anterior, side, ventral, and dorsal views, ×1, holotype USNM 118559. [Bell Canyon Formation (probably Hegler Member), USGS 2930.]

Bryorhynchus bisulcatum (Shumard): 6–8, Laterally tilted, posteriorly tilted, and interior views, ×3, showing threadlike median ridge, crura, and socket ridges, hypotype USNM 154909o; 10–12, interior, posteriorly tilted, and interior views of another brachial valve, ×3, showing cardinalia, hypotype USNM 154909m; 17, interior of the pedicle valve, ×2, showing pallial marks, hypotype USNM 154909k. [Bell Canyon Formation (Hegler Member), USNM 731.]

9, Anterior view of the interior, ×3, showing crura and median ridge, hypotype USNM 154910b. [Bell Canyon Formation (Pinery Member), USNM 725n.]

13–16, Interior and laterally tilted views, ×1.5, and the same views, ×4, showing crura and socket ridges, hypotype USNM 154908j. [Bell Canyon Formation (Rader Member), USNM 725f.]

Madarosia pentagona, new species: 18, Dorsal, side, anterior, and ventral views of a complete specimen, ×1, holotype USNM 154930 (for interior views see Plate 513: figures 39–41.) [Cherry Canyon Formation (Getaway Member), AMNH 512.]

Leiorhynchoidea amygdaloidea, new species: 19–23, Posterior, anterior, side, ventral, and dorsal views, ×1, holotype YPM 12552. [Word Formation (Willis Ranch Member), R. E. King 144.]

24, 25, Interior and exterior of a large pedicle valve, ×1, paratype USNM 148268a; 26, 27, preceding specimen posteriorly tilted to show dental plates, ×1, ×2; 28, posterior of the preceding specimen, ×2, showing disjunct deltidial plates. [Word Formation (lens between Willis Ranch and Appel Ranch members), USNM 706b.]

29–33, Posterior, anterior, side, ventral, and dorsal views of a young adult, ×1, paratype USNM 148282. [Word Formation (China Tank Member), USNM 721p.]

34, 35, Anterior views of the interior, ×3, showing the crura and median septum, paratype USNM 148265; 36–38, interior view, ×1, and laterally tilted and interior views, ×4, of a brachial valve, showing crura and median septum, paratype USNM 148263a. [Word Formation (Willis Ranch Member), USNM 706.]

PLATE 548.—Bryorhynchus, Leiorhynchoidea, and Madarosia.

PLATE 549

Leiorhynchoidea

Leiorhynchoidea scelesta, new species: 1, 2, 15, Dorsal, ventral, and side views of a young adult, ×1, paratype USNM 148276c. [Word Formation (Appel Ranch Member), USNM 715i.]

3–6, Anterior, laterally tilted, interior, and posteriorly tilted views, ×3, showing the crura and median septum, paratype USNM 152882f; 7, interior of the pedicle valve, ×1, showing the muscle scars and small deltidial plates, paratype USNM 152882t; 8, anterior view of a fragmentary brachial valve, ×1, paratype USNM 152882-1; 9, side view of a broken specimen, ×2, showing the median septum and crura, paratype USNM 152882w; 10, interior of a large brachial valve, ×2, showing a nearly fused hinge plate, paratype USNM 152882h; 11, anterior view of a young specimen, ×3, showing the crura and median septum, paratype USNM 152882k; 12–14, dorsal, ventral, and posterior views of a young adult, ×1, paratype USNM 152882b; 16–19, ventral, side, dorsal, and anterior views of a nearly full-grown adult, ×1, paratype 152882c; 20–24, ventral, anterior, side, dorsal, and posterior views of an adult, ×1, holotype USNM 152882d; 25–28, side, dorsal, anterior, and ventral views of a large adult, ×1, paratype USNM 152882e. [Word Formation (Appel Ranch Member), USNM 719z.]

PLATE 549.—Leiorhynchoidea.

PLATE 550

Leiorhynchoidea and Bryorhynchus

Leiorhynchoidea sulcata, new species: 1, 2, Dorsal and ventral views of a young individual, ×1, paratype USNM 154619b. [Cherry Canyon Formation (South Wells Member), AMNH 414.]

3–7, Dorsal, anterior, ventral, side, and posterior views of a round specimen, ×1, paratype USNM 155056a. [Cherry Canyon Formation (South Wells Member), USGS 7649.]

Bryorhynchus plicatum, new species: 8–12, posterior, anterior, side, dorsal, and ventral views, ×1, holotype USNM 153484a; 13, 14, posterior and dorsal views of an interior mold, ×1, showing the median septum, paratype USNM 153484b; 15–19, posterior, anterior, side, ventral, and dorsal views of a slightly crushed paratype, ×1, USNM 153484d. [Word Formation (Appel Ranch Member), USNM 731z.]

Leiorhynchoidea rotundidorsa, new species: 20, 21, Ventral and dorsal views of an immature specimen, ×1, paratype USNM 148285f; 22, interior of the preceding specimen, ×4, showing cardinalia (specimen unfortunately now broken in two pieces); 23, interior of a pedicle valve tilted to show the short dental plates, ×1, partype USNM 148285d; 24–27, side, anterior, exterior, and interior views of another pedicle valve, ×1, paratype USNM 148285c; 28–31, interior and exterior views, ×1, and posterior and interior views, ×2, showing cardinalia, paratype USNM 148285a; 32–35, exterior, interior, anterior, and side views of a brachial valve, ×1, holotype USNM 148285b; 36, 37, posterior and interior views of the preceding specimen, ×2, showing the cardinalia. [Cherry Canyon Formation (Getaway Member), USNM 728.]

Leiorhynchoidea scelesta, new species: 38, Ventral, posterior, side, anterior, and dorsal views of an immature individual, ×1, paratype USNM 154911a; 39–43, posterior, anterior, side, dorsal, and ventral views of a young specimen, ×1, paratype USNM 154911b; 44–46, ventral, side and dorsal views, ×1, of a young adult, paratype USNM 148276a. [Word Formation (Appel Ranch Member), USNM 715i.]

47, 48, Ventral and dorsal views of another young individual, ×1, paratype USNM 152882a; 49, 50, anterior view of the interior, ×1.5, ×1, showing the anteriorly expanding crura and their relation to the median seputm, paratype USNM 152882g; 51–53, ventral, posterior, side, anterior, and dorsal views of three immature individuals, ×1, paratypes USNM 152882o, p, q. [Word Formation (Appel Ranch Member), USNM 719z.]

PLATE 550.—Leiorhynchoidea and Bryorhynchus.

PLATE 551

Paranorella, Petasmatherus, and Anteridocus

Paranorella imperialis Cloud: 1–5, Posterior, anterior, side, dorsal, and ventral views of a complete specimen, ×1, hypotype USNM 148295a. [Permian (middle of the Waagenoceras Shale), 1 km south of Malascachas, Coahuila, Mexico.]

Paranorella aquilonia, new species: 6–10, Ventral, dorsal, posterior, side, and anterior views, ×1, holotype USNM 148296. [Cherry Canyon Formation (Getaway Member), AMNH 600.]

11, 12, Interior of the brachial valve, ×1, ×2, showing the small cardinalia, paratype USNM 148298. [Bell Canyon Formation (Lamar Member), AMNH 347.]

Paranorella comptula, new species: 13, 14, Ventral and dorsal views of a crushed individual, ×1, holotype USNM 148293; 15, interior of an imperfect pedicle valve, ×1, paratype USNM 148292a; 16, 17, posteriorly tilted and interior views of an imperfect brachial valve, ×1, showing the cardinalia, paratype USNM 148292b; 18, interior of a brachial valve, ×4, showing an incomplete hinge plate, paratype USNM 148292c. [Word Formation (China Tank Member), USNM 706c.]

Paranorella species 1: 19–22, Exterior, interior, side, and anterior views of a pedicle valve, ×1, figured specimen USNM 148290a; 23, 24, exterior and interior of another pedicle valve, ×1, figured specimen USNM 148290b; 25, interior of a pedicle valve, ×1.5, showing muscle scars and trace of pallial marks, figured specimen USNM 148290c; 27, 28, interior of the brachial valve, ×1, ×3, showing the cardinalia, figured specimen USNM 154912a; 29, interior of another fragment of a brachial valve, ×2, figured specimen USNM 154912b; 30, interior of a pedicle valve, ×1, showing the muscle field, figured specimen USNM 154912c. [Word Formation (lens between Willis Ranch and Appel Ranch members), USNM 706b.]

26, Interior of a pedicle valve, ×1, figured specimen USNM 148297. [Word Formation (Willis Ranch Member), USNM 706e.]

Paranorella species 2: 31, Interior of a brachial valve fragment, ×1, showing cardinalia, figured specimen USNM 152874a; 32, 33, interior of another fragmentary brachial valve, ×1, ×2, showing crura and median septum, figured specimen USNM 152874d; 34, interior of a pedicle valve, ×1, showing muscle scars, figured specimen USNM 152874c. [Bone Spring Formation, USNM 728f.]

47, Impression of the interior of the brachial valve, ×1, figured specimen USNM 152875. [Skinner Ranch Formation (Poplar Tank Member), USNM 729f.]

Petasmatherus pusillus (Girty): 35, Dorsal, anterior and side views, ×1, holotype USNM 118571; 36–39, ventral, anterior, side, and dorsal views, ×3, of the holotype; 40–42, anterior, dorsal, and side views, ×4, of the holotype. [Bell Canyon Formation (Pinery Member), USGS 2930.]

Anteridocus subcarinatus, new species: 43–46, Posterior, anterior, side, ventral, and dorsal views, ×1, and anterior, side, and dorsal views, ×2, holotype USNM 152980. [Bell Canyon Formation (Pinery Member), USNM 725n.]

PLATE 551.—Paranorella, Petasmatherus, and Anteridocus.

PLATE 552

Aphaurosia, Divaricosta, Cenorhynchia, Pontisia, Ptilotorhynchus, Phrenophoria, Deltarina, Antronaria, Fascicosta, and Madarosia

Aphaurosia scutata, new species: 1, Dorsal view of a complete specimen, ×1, paratype USNM 154913; 2–5, anterior, side, dorsal and ventral views of the preceding specimen, ×2. [Bell Canyon Formation (Lamar Member), USNM 728p.]

Divaricosta squarrosa, new species: 6, Exterior of a pedicle valve, ×2, showing intercalated and bifurcated costae, hypotype USNM 154675a; 7–9, anterior, dorsal, and side views of a complete specimen ×2, showing the overlapping lamellae at the anterior, paratype AMNH 27904/2; 10, posterior of the pedicle valve, ×5, showing the conjunct deltidial plates, hypotype USNM 154675b. [Cherry Canyon Formation. (Getaway Member), AMNH 512 ═ USNM 728.]

Cenorhynchia fracida, new species: 11–13, Dorsal, side, and anterior views of a complete specimen, ×3, paratype USNM 154721. [Word Formation (Willis Ranch Member), USNM 706e.]

Pontisia stehlii stehlii Cooper and Grant: 14, Ventral view of interior and the beak of same specimen, ×3, showing the undivided hinge plate and the conjunct deltidial plates, paratype USNM 154745j. [Cathedral Mountain Formation, USNM 726o.]

Ptilotorhynchus delicatum, new species: 15, Interior of the brachial valve, ×4, showing divided hinge plate and thick median ridge, paratype USNM 154712b; 16, dorsal view of an immature specimen, ×4, showing the reflected lip on the deltidial plates, paratype USNM 154712a. [Bell Canyon Formation (Lamar Member), USNM 728p.]

Phrenophoria vetula, new species: 17, Interior of the pedicle valve, tilted to show the dental plates, ×2, paratype USNM 154914. [Cathedral Mountain Formation, USNM 721u.]

Deltarina magnicostata, new species: 18–21, Dorsal, anterior, and side views, ×1, and dorsal view, ×2, of a complete, wide specimen, paratype USNM 154915. [Bell Canyon Formation (Lamar Member), USNM 728p.]

Antronaria mesicostalis (Girty): 22–26, Ventral, anterior, posterior, side, and dorsal views of a complete specimen, ×1, hypotype USNM 154511; 27–29, side, dorsal, and anterior views of the preceding specimen ×2. [Cibolo Formation (Breccia Zone of Udden), USNM 738s.]

Fascicosta bella, new species: 30–34, Dorsal, anterior, side, posterior, and ventral views, ×3, paratype USNM 154513a; 35, 36, posteriorly tilted and interior views, of the pedicle valve, ×2, showing dental plates and absence of deltidial plates, paratype USNM 154513b; 37, ventral view of the interior, ×6, showing long crura and low median ridge, paratype USNM 154513c. [Bell Canyon Formation (Rader Member), USNM 725f.]

Madarosia anterolamellata, new species: 38–41, Anterior, ventral, dorsal, and side views, ×1, of a young adult, paratype USNM 154916a; 42–47, posterior, side, dorsal, anterior, and ventral views, ×1, and anterior view of another young individual, ×2, paratype USNM 154916b; 48–53, dorsal, posterior, anterior, ventral, and side views, ×1, and anterior view, ×2, showing the anterior lamellae, paratype USNM 154916c; 54, anterior of another specimen in which the anterior lamellae have not yet developed, ×2, paratype USNM 154916d; 55, interior of the brachial valve, ×4, showing the small cardinalia and short hinge plate, paratype USNM 154916c; 56, interior of another fragmentary brachial valve, ×3, paratype USNM 154916f; 57, side view of a broken specimen, ×3, showing median septum and long, slender crura, paratype USNM 154916g; 58, interior of the pedicle valve tilted to show the small dental plates and lack of deltidial plates, ×3, paratype USNM 154916h. [Bell Canyon Formation (Rader Member), USNM 740j.]

PLATE 552.—Aphaurosia, Divaricosta, Cenorhynchia, Pontisia, Ptilotorhynchus, Phrenophoria, Deltarina, Antronaria, Fascicosta, and Madarosia.

PLATE 553

Tautosia, Stenoscisma, Wellerella, and Phrenophoria

Tautosia shumardiana (Girty) [hypotypes]: 1–3, Dorsal, side, and anterior views, ×1, small adult shell USNM 154920a; 4–6, dorsal, side, and anterior views, ×1, small adult shell USNM 154920b; 7–9, dorsal, side, and anterior views, ×1, adult shell USNM 154920c. [Bell Canyon Formation (Lamar Limestone Member), USNM 728p.]

Stenoscisma abbreviatum, new species: 10–14, Dorsal, ventral, side, posterior, and anterior views, ×1, adult paratype USNM 154918b; 15–20, dorsal views, ×1, ×2, ventral, side, posterior, and anterior views, ×1, adult holotype USNM 154918a; 21, interior view of pedicle valve with attached beak end of brachial valve with camarophorium, ×2, paratype USNM 154918c; 22, anterior view into interior of broken shell with spondylium and camarophorium, ×2, paratype USNM 154918d; 23, side oblique view of fragment of brachial valve with broad stolidium, ×1, paratype USNM 154918e; 27, interior view of pedicle valve with foramen and spondylium, ×2, paratype USNM 1549l8f. [Bell Canyon Formation (Lamar Limestone Member), USNM 728p.]

24–26, Dorsal views, ×1.5, ×1, ventral view, ×1, small adult shell with stolidium, paratype USNM 154917a. [Bell Canyon Formation (Lamar Limestone Member), AMNH 347 (═ L–2).]

Stenoscisma multicostum Stehli: 28–32, Dorsal, ventral, side, anterior, and posterior views, ×1, adult shell, hypotype USNM 154919a. [Cibolo Formation, USNM 738h.]

Wellerella girtyi girtyi, new subspecies: 33, Anterolateral view, ×3, showing the crura and undivided hinge plate, paratype USNM 154732n; 34, interior of the brachial valve, ×3, showing hinge plate and crura, paratype USNM 154732m. [Word Formation (Willis Ranch Member), USNM 706e.]

Phrenophoria subcarinata Cooper and Grant: 35, Side view of a brachial valve, ×1, hypotype USNM 148385g; 36, the same view, ×3, showing boring; 37, enlargement of boring and shell margin, ×6; 38, 39, two views, ×6, showing the protective tube surrounding the boring. [Word Formation (lens between the Willis Ranch and Appel Ranch members), USNM 706b.]

Tautosia elegans (Girty): 40, Interior of the brachial valve, ×3, showing the hinge plate, hypotype USNM 154921. [Bell Canyon Formation (Lamar Member), USNM 738.]

Tautosia transenna, new species: 41, Dorsal view of the interior, showing the underside of the hinge plate and crura, ×3, paratype USNM 154809c. [Word Formation (Willis Ranch Member), USNM 706e.]

42–44, Interior, posteriorly tilted, and laterally tilted views of the brachial valve, ×4.5, showing the fused hinge plate and long crura, paratype USNM 154807e. [Cherry Canyon Formation (Getaway Member), USNM 728.]

PLATE 553.—Tautosia, Stenoscisma, Wellerella, and Phrenophoria.

PLATE 554

Stenoscisma

Stenoscisma amoenum, new species: 1–7, Dorsal, ventral, side, posterior, and anterior views of holotype, ×2 (figures 2, 4, ×1), USNM 152271a; 8–14, Dorsal, ventral, side, posterior, and anterior views, ×2 (figures 9, 11, ×1), paratype USNM 152271b. [Skinner Ranch Formation (Decie Ranch Member), USNM 708q.]

Stenoscisma repigratum, new species: 15–22, Dorsal view, ×2, (figures 15, 22, ×1), holotype USNM 152281 (figure 21 shows interior with camarophorium and crus above edge of spondylium). [Word Formation (China Tank Member), USNM 706c.]

Stenoscisma aberrans, new species: 23, 24, Ventral views, ×1, ×2, showing spondylium and end of camarophorium, holotype USNM 152876a; 25–31, Dorsal, side, posterior, and anterior views of same specimen, ×2 (figures 25, 28, 30, ×1); 32, Ventral valve interior, ×1, paratype USNM 152876b. [Bell Canyon Formation (Rader Member), USNM 725f.]

PLATE 554.—Stenoscisma.

PLATE 555

Stenoscisma

Stenoscisma aptatum, new species: 1–4, Dorsal views of two nepionic shells, ×1, ×2, paratypes USNM 152241a, b; 5–9, dorsal, ventral, and side views, ×2, and dorsal and side views, ×1, of nepionic shell, paratype USNM 152241c; 10–14, dorsal, ventral, and side views of nepionic shell, ×1, ×2, paratype USNM 152241d; 15–20, dorsal, ventral, side, and anterior views of juvenile with incipient costae, ×1, ×2, paratype USNM 152241e; 21–26, dorsal, ventral, side, anterior, and posterior views, ×1, and ×2, juvenile paratype USNM 152241f; 27–33, dorsal, ventral, side, posterior, and anterior views of large, costate juvenile, ×1, ×2, paratype USNM 152241g. [Base of Road Canyon Formation, USNM 702c.]

34–40, Dorsal, ventral, side, posterior, and anterior views, ×1, ×2, subadult paratype USNM 152239. [Basal Cathedral Mountain Formation, USNM 702.]

41–47, Dorsal, ventral, posterior, anterior, and side views of adult with stolidium, ×1, ×2, holotype USNM 152240. [Base of Road Canyon Formation, USNM 702c.]

48–50, Dorsal view, ×1, ×2, and anterior ×2, of adult shell showing traces of successive stolidia, paratype USNM 152244. [Cathedral Mountain Formation (Institella Zone), USNM 703bs.]

PLATE 555.—Stenoscisma.

PLATE 556

Stenoscisma

Stenoscisma bonum, new species: 1–4, Dorsal, ventral, and side views, ×2 (figure 2, ×1) juvenile paratype USNM 152877j; 5–8, dorsal, ventral, and side views, ×2 (figure 6, ×1), juvenile paratype USNM 152877k; 9–12, dorsal, ventral, and side views, ×2 (figure 10, ×1), juvenile paratype USNM 152877m; 13–16, dorsal, ventral, and side views, ×2 (figure 14, ×1), juvenile paratype USNM 152877n; 17 dorsal interior, ×3, showing camarophorium, paratype USNM 152877o; 18, interior of broken shell, ×3, showing camarophorium and crus, paratype USNM 152877p; 19, dorsal interior of small adult, ×3, paratype USNM 152877q; 20, ventral interior ×3, showing spondylium, paratype USNM 152877r; 21–27, dorsal, ventral, side, anterior, and posterior views of adult with stolidium, ×1, ×2, holotype USNM 152877s. [Road Canyon Formation USNM 724j.]

28–33, Dorsal, ventral, side, and posterior views of adult with stolidium, ×1, ×2, paratype USNM 154575a. [Road Canyon Formation, USNM 724b.]

Stenoscisma bellatulum, new species: 34–38, Dorsal, ventral, and side views ×1, ×2, juvenile or small adult paratype USNM 154574a; 39, ventral interior, ×2, paratype USNM 154574b; 40, dorsal interior, ×2, paratype USNM 154574c; 41–47, dorsal, ventral, side, posterior, and anterior views, ×1, ×2, paratype USNM 154574d; 48–54, dorsal, ventral, side, anterior, and posterior views, ×1, ×2, holotype USNM 154574e. [Neal Ranch Formation (bed 4), USNM 727e.]

PLATE 556.—Stenoscisma.

PLATE 557

Stenoscisma

Stenoscisma calvatum, new species: 1–7, Dorsal, ventral, side, posterior, and anterior views, ×2, and dorsal and side views, ×1, nepionic paratype USNM 152340h; 8–14, dorsal, ventral, side, posterior, and anterior views, ×1, ×2, nepionic paratype USNM 152340i; 22, ventral interior, ×2, paratype USNM 152340o; 23, ventral interior ×2, showing pallial lines, paratype USNM 152340p; 32, dorsal interior, ×2, showing hinge plate, cardinal process, and camarophorium, paratype USNM 152340q; 33–39, dorsal, ventral, side, posterior, and anterior views, ×1, ×2, paratype USNM 152340j; 40–46, dorsal, ventral, side, posterior, and anterior views, ×1, ×2, paratype USNM 152340k; 47–53, dorsal, ventral, side, posterior, and anterior views, ×1, ×2, paratype USNM 152340m; 54–60, dorsal, ventral, side, posterior, and anterior views, ×1, ×2, holotype USNM 152340n. [Road Canyon Formation, USNM 721t.]

15–21, Dorsal, ventral, side, posterior, and anterior views, ×1, ×2, paratype USNM 152341f; 24–30, dorsal, ventral, side, posterior, and anterior views, ×1, ×2, paratype USNM 152341g; 31, side interior view, ×2, showing camarophorium and spondylium, paratype USNM 152341h. [Road Canyon Formation, USNM 721x.]

Stenoscisma inaequale (Girty): 61–67, Dorsal, ventral, side, posterior, and anterior views, ×1, ×2, holotype USNM 155138. [Bone Spring Formation, North Apache Canyon, Sierra Diablo, Texas, USGS 4643.]

PLATE 557.—Stenoscisma.

PLATE 558

Stenoscisma

Stenoscisma camurum, new species: 1–6, Dorsal, ventral, side, and anterior views, ×1, ×2, nepionic paratype USNM 154573a; 7–12, dorsal, ventral, side, and anterior views, ×1, ×2, juvenile paratype USNM 154573b; 13–18, dorsal, side, posterior, and anterior views, ×1, ×2, juvenile paratype USNM 154573c; 19–25, dorsal, ventral, posterior, side, and anterior views, ×1, ×2, juvenile paratype USNM 154573d; 39, anterior view of dorsal valve with two stolidia, ×1.4, paratype USNM 154573e; 42, lateral view of broken shell, ×1.4, showing interior with spondylium, crus, and camarophorium, paratype USNM 154573f. [Cherry Canyon Formation (Getaway Member), AMNH 585.]

26–29, Dorsal, side, and ventral views of paratype with large right stolidium, ×1, ×1.4, USNM 152237a; 30–34, dorsal, ventral, anterior, and side views, ×1, ×1.4, adult paratype USNM 152237b; 35–38, dorsal, ventral, and anterior views of adult with broad stolidium, ×1, ×1.5, holotype USNM 152878; 40, ventral interior, ×1.4, paratype USNM 152237c; 41, dorsal interior, ×2, paratype USNM 152237d. [Road Canyon Formation, USNM 707e.]

PLATE 558.—Stenoscisma.

PLATE 559

Stenoscisma

Stenoscisma doricranum, new species: 1–6, Dorsal, ventral, side, posterior, and anterior views, ×2 (figure 2, ×1), nepionic paratype USNM 152286a; 7–12, dorsal, ventral, side, posterior, and anterior views, ×2 (figure 8, ×1), nepionic paratype USNM 152286b; 13–18, dorsal, ventral, side, anterior, and posterior views, ×2, juvenile paratype USNM 152286c; 19–24, dorsal, ventral, side, anterior, and posterior views, ×2 (figure 20, ×1), juvenile paratype USNM 152286d; 25–30, dorsal, ventral, side, anterior, and posterior views, ×2 (figure 26, ×1), juvenile paratype USNM 152286e; 34–39, dorsal, ventral, side, inverted posterior, and anterior views, ×2 (figure 35, ×1), adult paratype USNM 152286f; 40–45, dorsal, ventral, side, inverted posterior, and anterior views, ×2 (figure 41, ×1), adult paratype USNM 152286g; 46–51, dorsal, ventral, side, inverted posterior, and anterior views,” ×2 (figure 47, ×1), adult holotype USNM 152286h; 52, dorsal interior, ×2, showing hinge plate, sockets, cardinal process, and camarophorium, paratype USNM 152286i; 53, articulated posterior part of shell, ×2, showing spondylium and camarophorium; paratype USNM 152286j; 54, articulated beak region, ×2, showing relationship of cardinal process to spondylium, paratype USNM 152286k. [Cathedral Mountain Formation (lower part), USNM 702a.]

31–33, Dorsal, ventral, and side views, ×1, adult paratype USNM 152285. [Cathedral Mountain Formation (near base), USNM 702.]

55, Side interior view of specimen that formed base for growth of bryozoan colony, in living position, ×1.5, paratype USNM 152291a. [Cathedral Mountain Formation (near base), USNM 702un.]

PLATE 559.—Stenoscisma.

PLATE 560

Stenoscisma

Stenoscisma exutum, new species: 1–7, Dorsal, ventral, side, posterior, and anterior views, ×1, ×2, juvenile paratype USNM 152296c; 8, anterolateral view, ×1, showing multiple stolidia, paratype USNM 152296g; 9, ventral interior, ×1, showing spondylium, paratype USNM 152296h; 11–17, dorsal, ventral, side, posterior, and anterior views, ×1, ×2, juvenile paratype USNM 152296i; 18–24, dorsal, ventral, side, anterior, and posterior views, ×1, ×2, small adult paratype USNM 152296j; 25–31, dorsal, ventral, side, anterior, and posterior views, ×1, ×2, adult holotype USNM 152296e. [Cathedral Mountain Formation (near base), USNM 702.]

10, Dorsal interior, ×1, showing cardinalia and camarophorium with intercamarophorial plate, paratype USNM 152301a; 32–38, dorsal, ventral, side, posterior, and anterior views, ×1, ×2, adult paratype USNM 152301b. [Cathedral Mountain Formation (near base), USNM 703b.]

PLATE 560.—Stenoscisma.

PLATE 561

Stenoscisma

Stenoscisma fabarium, new species: 1, Ventral interior, ×2, nepionic paratype USNM 152234a; 2, ventral interior, ×2, nepionic paratype USNM 152234b; 3–8, dorsal, ventral side, and anterior views, ×1, ×2, nepionic paratype USNM 152234c; 9–14, dorsal, ventral, side, and anterior views, ×1, ×2, juvenile paratype USNM 152234d; 15, ventral interior, ×2, juvenile paratype USNM 152234e; 16, dorsal interior, ×2, juvenile paratype USNM 152234f; 17–23, dorsal, ventral, side, anterior, and posterior views, ×1, ×2, juvenile paratype USNM 152234g; 24–30, dorsal, ventral, side, anterior, and posterior views, ×1, and ×2, juvenile paratype USNM 152234h; 34–40, dorsal, ventral, side, anterior, and posterior views, ×1, ×2, young adult paratype USNM 152234i; 41, ventral interior, ×2, showing pallial lines, young adult paratype USNM 152234j; 42–48, dorsal, ventral, side, anterior, and posterior views, ×1, ×2, adult paratype USNM 152234k; 49–55, dorsal, ventral, side, anterior, and posterior views, ×1, ×2, adult holotype USNM 152234-1; 56, anterolateral view, ×2, showing stolidium, adult paratype USNM 152234m; 57–63, dorsal, ventral, posterior, anterior, and side views, ×1, ×2, adult paratype USNM 152234n; 64, side view with dorsal valve broken to show profiles of camarophorium and crura, ×2, paratype USNM 152234o; 65–66, stereo pair of dorsal interior, ×2, showing cardinalia and camarophorium, paratype USNM 152234p; 67, dorsal interior, ×2, paratype USNM 152234q. [Cathedral Mountain Formation (near base), USNM 708u.]

31–33, Dorsal and side views, ×1, ×2, young adult paratype USNM 152233. [Cathedral Mountain Formation (base), USNM 702-low.]

PLATE 561.—Stenoscisma.

PLATE 562

Stenoscisma

Stenoscisma hadrum, new species: 1–4, Dorsal, ventral, side, and anterior views, ×1, nepionic paratype USNM 154576a. [Skinner Ranch Formation, USNM 726h.]

5–9, Dorsal, ventral, side, anterior, and posterior views, ×1, juvenile paratype USNM 152272; 10–12, dorsal, ventral, and side views, ×1, young adult paratype USNM 152274a; 13–15, dorsal, ventral, and side views, ×1, young adult paratype USNM 152274b; 25–28, dorsal, ventral, side, and anterior views, ×1, adult paratype USNM 152274d; 30–34, dorsal, ventral, side, anterior, and posterior views, ×1, adult holotype USNM 152274e. [Skinner Ranch Formation (near top), USNM 710r.]

16–19, Dorsal, ventral, side, and anterior views, ×1, (figure. 19: ×1.5), adult paratype USNM 154577a. [Hess Formation, USNM 726n.]

20–24, Dorsal, ventral, side, anterior, and posterior views, ×1, ×1.5, small adult paratype with stolidium, USNM 152267a; 29, dorsal interior, ×1, paratype USNM 152267c; 35–36, dorsal interior, straight, and oblique views, ×1, showing camarophorium and pallial lines on stolidium, paratype USNM 152267c (opposite valve of figure 29); 37–39, dorsal, side, and anterior views, ×1, ×1.5, adult paratype USNM 152267b. [Hess Formation (Taylor Ranch Member), USNM 702e.]

40, Fragment of dorsal exterior, ×1, showing broad stolidium, paratype USNM 152275. [Skinner Ranch Formation (Decie Ranch Member), USNM 715a.]

PLATE 562.—Stenoscisma.

PLATE 563

Stenoscisma

Stenoscisma hueconianum (Girty); 1–7, Dorsal, ventral, side, posterior, and anterior views, ×1, ×2, juvenile hypotype USNM 152247a; 8–14, dorsal, ventral, side, posterior, and anterior views, ×1, ×2, juvenile hypotype USNM 152247b; 15–21, dorsal, ventral, side, posterior, and anterior views, ×1, ×2, young adult hypotype USNM 152247c; 22–28, dorsal, ventral, side, posterior, and anterior views, ×1, ×2, adult hypotype USNM 152247d. [Alacran Mountain Formation, USNM 712e.]

29, Interior view of pedicle valve, ×2, hypotype USNM 154578a; 30–32, interior views of brachial valve, ×2, hypotypes USNM 154578b–d; 33, oblique interior view of broken shell, ×2, hypotype USNM 154578e; 34–40, dorsal, ventral, side, posterior, and anterior views, ×1, ×2, adult holotype USNM 155137; 41–47, dorsal, ventral, side, posterior, and anterior views of adult shell, ×1, ×2, hypotype USNM 154578f; 48–54, dorsal, ventral, side, anterior, and posterior views of adult shell with stolidium, ×1, ×2, hypotype USNM 154578g. [Alacran Mountain Formation, USNM 741h.]

PLATE 563.—Stenoscisma.

PLATE 564

Stenoscisma

Stenoscisma levicostum, new species: 1–5, Dorsal views, ×2, ×1, ventral, side, and anterior views, ×2, nepionic paratype USNM 152879i; 6–10, dorsal views, ×2, ×1, ventral, side, and anterior views, ×2, juvenile paratype USNM 152879a; 11–17, dorsal, ventral, side, anterior, and posterior views, ×1, ×2, juvenile paratype USNM 152879j; 18–24, dorsal, ventral, side, posterior, and anterior views, ×1, ×2, young adult paratype USNM 152879k; 40, side view of adult with stolidium, ×1, paratype USNM 152879m; 41, interior view of pedicle valve, ×1, paratype USNM 152879-1. [Bone Spring Formation (lower), USNM 728g.]

25–31, Dorsal, ventral, side, anterior, and posterior views, ×1, ×2, adult paratype USNM 154579a; 32–38, dorsal, side, ventral, anterior, and posterior views, ×1, ×2, adult holotype USNM 154579b; 39, side oblique view of broken shell, ×2, showing spondylium, camarophorium, and crus, paratype USNM 154579c. [Bone Spring Formation (lower) AMNH 591.]

PLATE 564.—Stenoscisma.

PLATE 565

Stenoscisma

Stenoscisma “deloi” (R. E. King): 1–5, Dorsal, ventral, side, posterior, and anterior views, ×1, specimen illustrated as Camarophoria deloi by King (1931, pl. 34: fig. 26), YPM 12694a; 6–10, dorsal, ventral, side, posterior, and anterior views, ×1, additional specimen from same locality but not illustrated by King, YPM 12694b. [Sawmill Canyon, Santa Rita Mountains, near onyx mine, 40 miles south of Tucson, Arizona.]

11–15, Dorsal, ventral, side, posterior, and anterior views, ×1, specimen illustrated as Camarophoria deloi by King 1931 (pl. 34: figs. 25a–c), YPM 12693 (now considered S. maniculum, new species, q.v.). [Road Canyon Formation (First Limestone Member of Word Formation, of P. B. King, 1931 ═ Road Canyon Formation), R. E. King 241.]

Stenoscisma maniculum, new species: 16–22, Dorsal, ventral, side, anterior, and posteroir views, ×1, ×2, holotype USNM 152305a; 23, interior of articulated shell, broken to show spondylium and camarophorium, ×2, paratype USNM 152305b. [Road Canyon Formation, USNM 706f.]

Stenoscisma kalum Stehli [all hypotypes]: 24–26, Ventral views, ×1, ×2, and side view, ×2, of ventral valve, USNM 142519b; 27, dorsal interior, ×1, also illustrated by Grant (1965, pl. 19: fig. 4), USNM 142520a; 28, interior of ventral valve with median stolidium, ×1, also illustrated by Grant (1965, pl. 19: fig. 4), USNM 142519a; 29–30, ventral interior, ×2, ×1, showing teeth and spondylium, USNM 142519c; 31, dorsal exterior, ×2, USNM 142520b; 32, interior of broad ventral valve, ×2, USNM 142519d. [Bone Spring Formation, USNM 728f.]

Stenoscisma multicoslum Stehli [all hypotypes]: 33–39, Dorsal, ventral, anterior, side, and posterior views of large adult, ×1, and ×1.5, USNM 152880. [Cibolo Formation, USNM 728m.]

40–41, Ventral and side views of ventral valve ×1, also illustrated by Grant (1965, pl. 19: fig. 3) USNM 142515a; 42–43, dorsal and side views of dorsal valve, ×1, also illustrated by Grant (1965, pl. 19: fig. 3a) USNM 142518a; 44, interior view of asymmetrical dorsal valve with camarophorium, stolidium, ×1.5, USNM 142518b; 45, interior view broken ventral valve with spondylium, transverse gonocoel grooves, ×1.5, USNM 142515b. [Bone Spring Formation, USNM 728f (═ AMNH 629).]

PLATE 565.—Stenoscisma.

PLATE 566

Stenoscisma

Stenoscisma myioides, new species: 1–7, Dorsal, ventral, side, posterior, and anterior views, ×1.5, ×3, nepionic paratype USNM 154580a; 8–14, dorsal, ventral, side, posterior, and anterior views, ×1.5, ×3, nepionic paratype USNM 154580b; 15–21, dorsal, ventral, side, posterior, and anterior views, ×1.5, ×4.5, juvenile paratype USNM 154580c; 25–31, dorsal, ventral, side, anterior, and posterior views, ×1.5, ×4.5, young adult paratype USNM 154580d; 32–37, dorsal, ventral, side, and posterior views, ×1.5, ×4.5, young adult paratype USNM 154580e. [Skinner Ranch Formation, USNM 716q.]

22, Ventral interior, ×3, paratype USNM 152217a; 23–24, dorsal-interior side and straight views, ×3, showing camarophorium, cardinalia, and pallial lines, paratype USNM 152217b; 38–44, dorsal, ventral, side, anterior, and posterior views, ×1, ×3, adult paratype USNM 152218c; 45–51, dorsal, ventral, posterior, side, and anterior views, ×1, ×3, adult holotype USNM 152218d; 52–57, dorsal, ventral, side and posterior views of slightly deformed adult paratype, ×1, ×3, USNM 152218b. [Skinner Ranch Formation (base ═ Decie Ranch Member), USNM 705a.]

PLATE 566.—Stenoscisma.

PLATE 567

Stenoscisma

Stenoscisma oblisum, new species: 1–7, Dorsal, ventral, side, anterior, and posterior views, ×1, ×2, nepionic paratype USNM 152284a; 14–20, dorsal, ventral, side, anterior and posterior views, ×1, ×2, elongate juvenile paratype USNM 152263a; 21–27, dorsal, ventral, side, anterior, and posterior views, ×1, ×2, juvenile paratype USNM 152284b; 42–48, dorsal, ventral, anterior, posterior, and side views, ×1, ×2, juvenile paratype USNM 152284c; 49–55, dorsal, ventral, side, anterior, and posterior views, ×1, ×2, adult paratype USNM 152263b; 56–61, dorsal, ventral, side, and anterior views, ×1, ×2, elongate adult paratype USNM 152284d; 62–68, dorsal, ventral, side, anterior, and posterior views, ×1, ×2, adult holotype USNM 152284e. [Capitan Formation, USNM 739.]

8–13, Ventral, dorsal and side views, ×1, ×2, nepionic paratype USNM 152264a; 28–34, dorsal, ventral, side, posterior, and anterior views, ×1, ×2, juvenile paratype USNM 152264b; 35–41, dorsal, ventral, side, anterior, and posterior views, ×1, ×2, juvenile paratype USNM 152264c. [Capitan Formation, USNM 740.]

PLATE 567.—Stenoscisma.

PLATE 568

Stenoscisma

Stenoscisma pansum, new species: 1–7, Dorsal, ventral, side, anterior, and posterior views, ×1, ×2, juvenile paratype USNM 152258a; 8–14, dorsal, ventral, side, anterior, and posterior views, ×1, ×2, paratype USNM 152258b; 17–23, dorsal, ventral, anterior, posterior, and side views, ×1, ×2, adult paratype USNM 152258c; 33–39, dorsal, ventral, side, anterior, and posterior views, ×1, ×2, adult holotype USNM 152258d. [Skinner Ranch Formation (base), USNM 712p.]

15–16, Dorsal and side views, ×1, young adult paratype USNM 152254. [Skinner Ranch Formation (Decie Ranch Member), USNM 707w.]

24–27, Dorsal, ventral, side, and anterior views, ×1, adult paratype USNM 152257a; 28–32, dorsal, ventral, side, and anterior views, ×1.5, adult paratype USNM 152257b. [Skinner Ranch Formation (base), USNM 711d.]

40–42, Dorsal and side views, ×1, ×2, adult paratype USNM 152255. [Skinner Ranch Formation (Sullivan Peak Member) USNM 708e.]

PLATE 568.—Stenoscisma.

PLATE 569

Stenoscisma

Stenoscisma peneleve, new species: 1–9, Dorsal views, ×3, ×1, ×2, and ventral, side posterior, and anterior views, ×1, ×2, juvenile paratype USNM 152256a; 10–18, dorsal views, ×3, ×1, ×2, and ventral, side, posterior, and anterior views, ×1, ×2, juvenile paratype USNM 152256b; 19–27, dorsal views, ×3, ×1, ×2, and ventral, side, posterior, and anterior views, ×1, ×2, young adult paratype USNM 152256c. [Neal Ranch Formation, USNM 715b.]

28–36, Dorsal views, ×3, ×1, ×2, and ventral, side, posterior, and anterior views, ×1, ×2, adult holotype USNM 152261a; 37–44, dorsal, ventral, side, posterior, and anterior views, ×1, ×2, weathered paratype USNM 152261b. [Lenox Hills Formation, USNM 709t.]

Stenoscisma thevenini R. E. King (not Kozlowski): 45–52, Dorsal, ventral, side, posterior, and anterior views, ×1, ×2, specimen illustrated by R. E. King (1931, pl. 34: fig. 28a–c), YPM 12695. [“Leonard Formation,” R. E. King 123.]

PLATE 569.—Stenoscisma.

PLATE 570

Stenoscisma

[All ×1]

Stenoscisma problematicum, new species: 1–4, Ventral, side, posterior, and anterior views, nepionic paratype USNM 154581a; 5–9, dorsal, ventral, side, posterior, and anterior views, juvenile paratype USNM 154581b; 20–21, dorsal and side oblique views, paratype with stolidium USNM 154581c; 22–24, dorsal, side, and anterior views, adult paratype USNM 154581d; 25–29, dorsal, ventral, side, posterior, and anterior views, adult paratype USNM 154581e; 30–34, dorsal, ventral, side, posterior, and anterior views, adult paratype USNM 154581f; 35–39, dorsal, ventral, anterior, posterior, and side views, adult holotype USNM 154581g. [Skinner Ranch Formation (Decie Ranch Member), USNM 727u.]

10–14, Dorsal, ventral, side, posterior, and anterior views, juvenile paratype USNM 152197b; 15–19, Dorsal, ventral, side, posterior, and anterior views, young adult paratype USNM 152197c. [Skinner Ranch Formation (Decie Ranch Member), USNM 707a.]

40–44, Dorsal, ventral, side, anterior, and posterior views, adult paratype USNM 154582. [Cibolo Formation (Breccia Zone of Udden), USNM 728-1.]

PLATE 570.—Stenoscisma.

PLATE 571

Stenoscisma

Stenoscisma pyraustoides, new species: 1–7, Dorsal, ventral, side, posterior, and anterior views, ×1, ×1.5, juvenile paratype USNM 152220b; 8–14, dorsal, ventral, side, posterior, and anterior views of adult paratype with stolidium, ×1, ×1.5, USNM 152220c; 15–20, dorsal, ventral, side and posterior views, ×1, ×1.5, young adult paratype USNM 152219a; 21–22, side and interior views of ventral valve, ×2, paratype USNM 152219b; 30–31, side oblique and facing views of dorsal valve with camarophorium, cardinalia, and pallial trunks, ×2, paratype USNM 152220k; 37, fragment of anterior margin in ventral view, ×1.5, showing exterior of broken ventral stolidium, and inside of opposing dorsal stolidium with growth lines and narrowly spaced pallial lines, paratype USNM 152219c. [Skinner Ranch Formation (base), USNM 705a.]

23–29, Dorsal, ventral, side, posterior, and anterior views, ×1, ×1.5, adult paratype USNM 152221a; 32–36, dorsal, ventral, side, and posterior views, ×1, ×1.5, large juvenile paratype USNM 152221b. [Skinner Ranch Formation (base), USNM 705b.]

PLATE 571.—Stenoscisma.

PLATE 572

Stenoscisma

Stenoscisma pyraustoides, new species: 1–6, Dorsal, ventral, right side, left side, and anterior views, ×1, (figure 2, ×1.5), adult holotype with cemented coral, USNM 152220i; 12–17, dorsal, ventral, posterior, side, and anterior views, ×1.5 (figure 14, ×1), thin-shelled adult paratype USNM 152219d. [Skinner Ranch Formation (base), USNM 705a.]

7–11, Dorsal, ventral, side, and anterior views, ×1, (figure 8, ×1.5), large adult paratype USNM 152225.[Hess Formation (Taylor Ranch Member), USNM 716o.]

PLATE 572.—Stenoscisma.

PLATE 573

Stenoscisma

[All ×1, ×1.5]

Stenoscisma renode, new species: 1–7, Dorsal, ventral, side, anterior, and posterior views, nepionic paratype USNM 152210c; 8–13, dorsal ventral, side, posterior, and anterior views, juvenile paratype USNM 152210e; 14–20, dorsal, ventral, posterior, side, and anterior views, young adult paratype with stolidium, USNM 152209c; 21–27, dorsal, ventral, side, posterior, and anterior views, young adult paratype with several stolidia, USNM 152209d; 28–34, dorsal, ventral, side, anterior, and posterior views, adult paratype USNM 152209e; 35–41, dorsal, ventral, posterior, side, and anterior views, adult paratype USNM 152209f; 42–48, dorsal, ventral, side, posterior, and anterior views, adult paratype USNM 152209g. [Word Formation (limestone lens between Willis Ranch and Appel Ranch members), USNM 706b.]

PLATE 573.—Stenoscisma.

PLATE 574

Stenoscisma

[All ×1, ×1.5]

Stenoscisma renode, new species: 1–8, Dorsal, ventral, left side, posterior, anterior, and right side, narrow adult paratype with multiple stolidia and epifauna, USNM 152209a; 9–15, dorsal, ventral, anterior, posterior, and side views, adult holotype 152210i; 16–22, dorsal, ventral, side, anterior, and posterior views, adult paratype USNM 152209b. [Word Formation (limestone lens between Willis Ranch and Appel Ranch members), USNM 706b.]

PLATE 574.—Stenoscisma.

PLATE 575

Stenoscisma

Stenoscisma renode, new species: 1–2, Dorsal interior, ×2, and enlargement, ×4, of camarophorium and cardinalia, paratype USNM 152211a; 5–6, enlargement of camarophorium, ×4, showing muscle marks and cardinal process with striae, and dorsal interior, ×2, paratype USNM 152211b; 12–13, ventral interior, ×2, and enlargement, ×4, of spondylium, showing muscle marks, paratype USNM 152211c; 19, articulated shell broken to show underside of camarophorium, its septum, underside of hinge plate, the crura, and part of ventral spondylium, ×2, paratype USNM 152211d. [Word Formation (middle part of China Tank Member), USNM 706c.]

3–4, Dorsal, interior, ×2, and enlargement, ×4, of hinge plate, cardinal process, and camarophorium with muscle marks, paratype-USNM 152209h; 7–8, enlarged cardinal region, ×4, and dorsal valve, ×2, elongate muscle marks and intercamarophorial plate apparent, paratype USNM 152209i; 9, interior view of ventral valve, ×2, showing spondylium with muscle marks, paratype USNM 152209j; 10 interior view of pedicle valve, ×2, paratype USNM 152209k; 11, interior of another pedicle valve, ×2, paratype USNM 152209p; 14–15, dorsal interior, ×2, and enlargement, ×4, of cardinalia and camarophorium, paratype USNM 152209-1; 16, side view of articulated posterior part of shell with spondylium, camarophorium, and crura, ×2, paratype USNM 152209m; 17, anterior oblique view of interior, ×2, showing camarophorium and spondylium, paratype USNM 152209n; 18, side view of articulated fragment, ×2, showing close juxtaposition of camarophorium and spondylium, paratype USNM 152209o. [Word Formation (limestone lens between Willis Ranch and Appel Ranch members), USNM 706b.]

PLATE 575.—Stenoscisma.

PLATE 576

Stenoscisma

Stenoscisma trabeatum, new species: 1–7, Dorsal, ventral, side, anterior, and posterior views, ×1, ×1.5, adult paratype USNM 152230a; 15–21, dorsal, ventral, side, anterior, and posterior views, ×1, ×1.5 adult paratype USNM 152230c; 22–28, dorsal, ventral, side, posterior, and anterior views, ×1, ×1.5, adult holotype USNM 152230b. [Bell Canyon Formation (Lamar Member), USNM 738.]

8–14, Dorsal, ventral, side, anterior, and posterior views, ×1, ×1.5, adult paratype USNM 154586. [Bell Canyon Formation (Lamar Member), AMNH 347.]

29–30, ventral and posterior views of posterior part of ventral valve, ×1.5, showing posterolateral pockets, paratype USNM 154587. [Bell Canyon Formation (Lamar Member), AMNH 37.]

31, Interior view of ventral valve with posterolateral pockets, ×1.5, paratype USNM 154588. [Bell Canyon Formation (Lamar Member), USNM 725e.]

PLATE 576.—Stenoscisma.

PLATE 577

Stenoscisma

Stenoscisma venustum (Girty): 1–8, Dorsal, ventral, side, posterior, and anterior views, ×1, ×2, holotype USNM 118557. [Possibly the “Delaware Mountain Formation” Comanche Canyon, Glass Mountains, USGS 3763 (green); correct formation and locality unknown (see Girty, 1909:512)]

Stenoscisma trabeatum, new species: 9–15, Dorsal, ventral, side, anterior, and posterior views, ×1, ×1.5, of fragile and slightly crushed adult paratype USNM 152231a; 16–21, ventral, dorsal, ventral oblique, posterior, and anterior views of adult paratype with hole in ventral valve, ×1, ×1.5, showing crura and camarophorium inside, USNM 152230d; 23, ventral view of shell with part of ventral valve broken to expose cardinalia and camarophorium of dorsal valve, ×1.5, paratype USNM 152231b; 24, side view of broken shell, ×1.5, showing profile of camarophorium, paratype USNM 152231c. [Bell Canyon Formation (Lamar Member), USNM 738.]

22, Interior view of dorsal valve with broad stolidium, ×1.5, showing cardinalia and broken camarophorium with intercamarophorial plate, USNM 154585a. [Bell Canyon Formation (Lamar Member), USNM 728p.]

PLATE 577.—Stenoscisma.

PLATE 578

Stenoscisma

Stenoscisma triquetrum, new species: 1–8, Dorsal, ×1, ×2, ×3, and side, ventral, posterior, and anterior views, ×1, ×2, nepionic paratype USNM 152190a; 9–16, dorsal, ×1, ×2, ×3, and ventral, side, anterior, and posterior views, ×1, ×2, nepionic paratype 152190b; 17–24, dorsal, ×1, ×2, ×3, and side, posterior, ventral, and anterior views, ×1, ×2, nepionic paratype USNM 152190c; 25–32, dorsal, ×1, ×2, ×3, and side, ventral, posterior, and anterior views, ×1, ×2, nepionic paratype USNM 152190d; 33–39, dorsal, side, ventral, posterior, and anterior views, ×1, ×2, juvenile paratype USNM 152190e; 40–46, dorsal, side, ventral, posterior, and anterior views, ×1, ×2, juvenile paratype USNM 152190f; 47–53, dorsal, side, ventral, anterior, and posterior views, ×1, ×2, juvenile paratype USNM 152190g; 54–60, dorsal, side, ventral, anterior, and posterior views, ×1, ×2, juvenile paratype USNM 152190h; 61–67, dorsal, ventral, side, anterior, and posterior views, ×1, ×2, juvenile paratype USNM 152190i; 68–76, dorsal, ventral, right side, left side, posterior, and anterior views, ×1, ×1.5, adult paratype USNM 152190j. [Road Canyon Formation (base), USNM 702c.]

77, Side oblique view, ×1.5, showing camarophorium, crus, and spondylium, paratype USNM 142545 (illustrated by Grant, 1965, pl. 23: fig. 4, as S. venustum (Girty)); 79, oblique interior view of dorsal valve with camarophorium, crura, and cardinal process, ×2, paratype USNM 152334f. [Road Canyon Formation, USNM 719x.]

78, Side oblique view of interior of broken shell, ×2, showing camarophorium, crura, and spondylium, paratype USNM 152318b. [Cathedral Mountain Formation, USNM 702.]

PLATE 578.—Stenoscisma.

PLATE 579

Stenoscisma

Stenoscisma triquetrum, new species: 1, Dorsal view, ×2, nepionic paratype USNM 142533. 2, side view, ×2 nepionic paratype USNM 142534; 3–4, dorsal and side views, ×2, nepionic paratype USNM 142535; 5, dorsal view, ×2, nepionic paratype USNM 142536; 6, side view, ×2, nepionic paratype USNM 142537; 7–8, dorsal and side views, ×2, juvenile paratype USNM 142538; 9–10, dorsal and side views, ×2, juvenile paratype USNM 142540; 11–13, dorsal, anterior, and side views, ×2, juvenile paratype USNM 142541; 14–20, dorsal, ventral, posterior, side, and anterior views, ×1, ×2, young adult paratype with epifauna, USNM 152190k; 22–25, dorsal view, ×1.5, and anterior, posterior, and side views, ×1, adult paratype USNM 142528; 26–32, dorsal, ventral, side, anterior, and posterior views, ×1, ×1.5, mature adult paratype USNM 152190-1. [Road Canyon Formation (base), USNM 702c.]

21, Dorsal view, ×1, adult paratype USNM 152334e. [Road Canyon Formation, USNM 719x.]

PLATE 579.—Stenoscisma.

PLATE 580

Stenoscisma

Stenoscisma triquetrum, new species: 1–4, Dorsal, side, posterior, and anterior views, ×1, young adult paratype USNM 154589a; 5–8, dorsal, ventral, side, and posterior views, ×1, adult paratype USNM 154589b; 9–15, dorsal, ventral, side, anterior, and posterior views, ×1, ×1.5, adult paratype USNM 154589c. [Road Canyon Formation (lower part), USNM 726za.]

16–22, Dorsal, ventral, side, anterior, and posterior views, ×1, ×1.5, adult paratype USNM 152320b; 23–29, dorsal, ventral, side, anterior, and posterior views, ×1, ×1.5, adult paratype USNM 152320c. [Cathedral Mountain Formation, USNM 702b.]

30–36, Dorsal, ventral, side, posterior, and anterior views, ×1, ×1.5, adult paratype USNM 152334g. [Road Canyon Formation, USNM 719x.]

PLATE 580.—Stenoscisma.

PLATE 581

Stenoscisma

Stenoscisma triquetrum, new species: 1–7, Dorsal, ventral, posterior, side and anterior views, ×1, ×1.5, adult paratype USNM 152320a. [Cathedral Mountain Formation, USNM 702b.]

8–12, Dorsal, ventral, and side views, ×1, ×1.5, adult paratype USNM 152318c. [Cathedral Mountain Formation, USNM 702.]

13–19, Dorsal, ventral, side, anterior, and posterior views, ×1, ×1.5, adult holotype, USNM 152191U. [Road Canyon Formation (base), USNM 702c.]

PLATE 581.—Stenoscisma.

PLATE 582

Stenoscisma

Stenoscisma triquetrum, new species: 1–7, Dorsal, ventral, anterior, side, and posterior views, ×1, ×1.5, large juvenile paratype USNM 152334b. [Road Canyon Formation, USNM 719x.]

8, Interior view of broken paratype, ×2, USNM 142526. [Road Canyon Formation (base), USNM 721o.]

9, Dorsal interior, ×1, showing camarophorium and cardinalia, paratype USNM 152318d; 10, side oblique view of shell broken to show relationship of camarophorium and crura to spondylium, ×1.5, paratype USNM 142547; 11–12, side and facing views of dorsal interior, ×2, showing camarophorium, crura, and cardinalia, paratype USNM 142543; 14, side oblique view of broken shell, ×2, showing spondylium and relatively low camarophorium, paratype USNM 152318a; 15, ventral interior, ×1, showing spondylium and genital grooves, paratype USNM 142531; 16, ventral interior, ×2, juvenile paratype USNM 142542. [Cathedral Mountain Formation, USNM 702.]

13, Interior view of articulated posterior part of shell, covered with drusy quartz, ×2, showing internal structures, paratype USNM 152190m; 17–22, dorsal view, ×1, ×1.5, and ventral, side, posterior, and anterior views, ×2, adult paratype USNM 152190n. [Road Canyon Formation (base), USNM 702c.]

PLATE 582.—Stenoscisma.

PLATE 583

Stenoscisma

[All ×1 and ×2]

Stenoscisma species undetermined: 1–7, Dorsal, ventral, side, posterior, and anterior views, figured specimen, USNM 152317. [Bell Canyon Formation (Lamar Member), USNM 738.]

Stenoscisma species 2: 8–14, Dorsal, ventral, side, posterior, and anterior views, paratype USNM 152227a; 15–21, dorsal, ventral, side, posterior, and anterior views, paratype USNM 152227b. [Lenox Hills Formation, USNM 716r.]

Stenoscisma species 1: 22–28, Dorsal, ventral, side, posterior, and anterior views, paratype USNM 152280a; 29–35, dorsal, ventral, side, anterior, and posterior views, paratype USNM 152280b. [Hueco Formation, USGS 9999.]

36–42, Dorsal, ventral, side, anterior, and posterior views, USNM 152279a. [Lenox Hills Formation, USNM 730a.]

PLATE 583.—Stenoscisma.

PLATE 584

Torynechus

[All ×1, and ×2]

Torynechus alectorius, new species: 1–6, Dorsal, ventral, side, anterior, and posterior views, juvenile paratype USNM 154590a; 7–13, dorsal, ventral, side, anterior, and posterior views, broken juvenile paratype USNM 154590b; 14–20, dorsal, ventral, side, anterior, and posterior views, juvenile paratype USNM 154590c; 21–27, dorsal, ventral, side, anterior, and posterior views, young adult paratype USNM 154590d; 28–34, dorsal, ventral, side, anterior, and posterior views, mature adult paratype USNM 154590e; 35–41, dorsal, side, ventral, anterior, and posterior views, mature adult holotype USNM 154590f. [Skinner Ranch Formation (top), USNM 710r.]

PLATE 584.—Torynechus.

PLATE 585

Torynechus

Torynechus caelatus Cooper and Grant [all hypotypes]: 1–4, Dorsal, side, and anterior views, ×1, ×1.5, adult, USNM 142553; 5–11, Dorsal, ventral, side, anterior, and posterior views, ×1, ×2, young adult USNM 154593a; 12–18, dorsal, ventral, side, anterior, and posterior views, ×1, ×2, adult shell USNM 154593d; 26–32, dorsal, ventral, side, anterior, and posterior views, ×1, ×2, thick adult USNM 154593f. [Cathedral Mountain Formation (base), USNM 702un.]

19–25, Dorsal, ventral, side, anterior, and posterior views, ×1, ×2, well-preserved adult shell USNM 152594a; 33, anterior view of articulated shell broken to expose spondylium, camarophorium, and crura, ×2, USNM 152594b. [Cathedral Mountain Formation (base), USNM 703b.]

PLATE 585.—Torynechus.

PLATE 586

Psilocamara and Torynechus

Psilocamara hesperia, new species: 1–4, Dorsal and posterior views, ×1.5, ×4, paratype USNM 148188a; 5–8, dorsal and side views, ×1.5, ×4, paratype USNM 148188b; 9–12, dorsal and anterior views, ×1.5, ×4, holotype USNM 148188c. [Neal Ranch Formation, USNM 701-1.]

13, Interior view of ventral valve with spondylium, ×4, paratype USNM 154590a; 14, interior view of broken shell with camarophorium, ×4, paratype USNM 154590b. [Neal Ranch Formation, USNM 701a^3.]

Torynechus caelatus Cooper and Grant [all hypotypes]: 15–21, Dorsal, ventral, side, anterior, and posterior views, ×1, ×2, USNM 154591. [Cathedral Mountain Formation, AMNH 504.]

22–25, Broken shell with camarophorium and cardinalia seen in ventral, anterior oblique, ventral oblique, and side oblique views, ×2, USNM 154593j; 26, ventral interior with spondylium and genital grooves, ×2, USNM 154593k; 28, articulated posterior part of shell with camarophorium, crura, and spondylium, ×2, USNM 154593m; 29, shell with dorsal valve broken to show underside of camarophorium, and dichotomous pallial lines, ×2, USNM 154593-1. [Cathedral Mountain Formation (base), USNM 702un.]

27, Ventral interior with weak muscle marks in spondylium, ×2, USNM 152595a. [Cathedral Mountain Formation (base) USNM 702.]

PLATE 586.—Psilocamara and Torynechus.

PLATE 587

Xenosaria, Grandaurispina, and Crurithyris

Xenosaria exotica, new species: 1–5, Dorsal, anterior, side, posterior, and ventral views of a small complete specimen, ×1, paratype USNM 153460b; 6–15, ventral, anterior, side, posterior, and dorsal views, ×1, and ventral, anterior, side, posterior, and dorsal views, ×2, of another complete specimen, paratype USNM 153460a; 27–30, interior tilted, interior, posterior, and side views of a brachial valve, ×4, showing the cardinalia, paratype USNM 153460c. [Bell Canyon Formation (Hegler Member), USNM 732a.]

16–20, Dorsal, anterior, posterior, ventral, and side views, holotype USNM 153459e; ×1, 21, interior of pedicle valve, ×2, paratype USNM 153459h; 22–26, dorsal, posterior, side, ventral, and anterior views, ×2, of the holotype; 31, interior of the pedicle valve, ×4, paratype USNM 153459c; 32–34, posterior, interior, and oblique views of the brachial valve, ×4, paratype USNM 153459g. [Bell Canyon Formation (Hegler Member), USNM 731.]

Grandaurispina species (in volume III): 35–38, Posterior, anterior, side, and ventral views of the pedicle valve, ×1, figured specimen USNM 155046a; 39, posterior view of a small pedicle valve, ×1, figured specimen, USNM 155046b; 40, interior of the brachial valve, ×1, figured specimen USNM 155046c. [Cathedral Mountain Formation, USNM 721u.]

Crurithyris guadalupensis (Girty): 41, Dorsal, posterior, side, anterior, and ventral views of a small specimen, ×1, hypotype USNM 152430-1; 42, dorsal, posterior, side, anterior, and ventral views of another complete specimen, ×1, hypotype USNM 152430r; 58, oblique view, ×4, of a specimen showing the long descending process of the spire, hypotype USNM 154420a; 59, broken specimen, ×4, showing the descending process of the spire, hypotype USNM 154420b. [Bell Canyon Formation (Lamar Member), USNM 738b.]

43–48, Dorsal, posterior, side, anterior, and ventral views, ×1, and anterior, side, posterior, ventral, and dorsal views, ×2, of a complete specimen, hypotype USNM 152428b; 49–54, dorsal, posterior, side, anterior, and ventral views, ×1, and posterior, side, anterior, ventral, and dorsal views, ×2, of a complete specimen, hypotype USNM 152428a; 55, interior of a brachial valve, ×4, showing the descending lamellae of the spire and the cardinalia, hypotype USNM 152428d; 56, interior of another dorsal valve, ×4, showing cardinal process, hypotype USNM 152428e; 57, interior of ventral valve, ×3, hypotype USNM 152428f. [Bell Canyon Formation (Lamar Member), USNM 738.]

Crurithyris inflata Stehli: 60, Ventral, posterior, side, anterior, and dorsal views of a small specimen, ×1, hypotype USNM 152433o; 61, ventral, posterior, side, anterior, and dorsal views of another complete specimen, ×1, hypotype USNM 152433t; 62–65, dorsal, side, posterior, and anterior view of a complete specimen, ×2, hypotype USNM 152433q; 66–70, dorsal, posterior, side, anterior, and ventral views of a large complete specimen, ×2, hypotype USNM 152433w; 71–73, dorsal, ventral and side views of a complete specimen, ×2, hypotype USNM 152433u. [Bone Spring Formation, USNM 728f.]

PLATE 587.—Xenosaria, Grandaurispina, and Crurithyris.

PLATE 588

Crurithyris

Crurithyris longirostris, new species: 1–6, Ventral, posterior, side, anterior, and dorsal views, ×1, and posterior, anterior, ventral, side, and dorsal views, ×3, of a complete specimen, holotype USNM 152985d; 7, anterior of a complete specimen, showing anterior thick ends of the spire, ×4, paratype USNM 152985f. [Bone Spring Formation, AMNH 591.]

Crurithyris major, new species: 8–12, Anterior, posterior, side, dorsal, and ventral views, ×1, paratype USNM 152439j; 13–17, dorsal, anterior, posterior, ventral, and side views of a complete specimen, ×1, paratype USNM 152439d; 18–20, dorsal view, ×1, and dorsal and oblique views, ×3, of an immature specimen, paratype USNM 152439e; 26, 27, interior of the pedicle valve, ×5, ×1, showing lateral plates, paratype USNM 154421a; 28, posterior of a brachial valve, showing lateral plates and cardinalia, ×2, paratype USNM 154421b; 29, posterior of a pedicle valve, showing apical plate, ×3, paratype USNM 152439p; 30, posterior of another pedicle valve, ×3, showing lateral plates bordering the delthyrium, paratype USNM 154421d; 31, interior of a brachial valve preserving the descending lamellae of the spire, ×2, paratype USNM 154421c; 32, dorsal view of a large specimen, ×1, showing lateral plates, paratype USNM 152439o. [Word Formation (Appel Ranch Member), USNM 719z.]

21–25, Anterior, posterior, side, dorsal, and ventral views, ×1, of the holotype USNM 152437c. [Word Formation (Appel Ranch Member), USNM 715i.]

Crurithyris sulcata Stehli: 33, 34, Ventral, posterior, side, anterior, and dorsal views, ×1, and posterior view, ×3, showing lateral plates, hypotype USNM 152435d; 35–40, ventral, posterior, side, anterior, and dorsal views, ×1, and posterior, side, dorsal, anterior, and ventral views, ×2, of a complete specimen, hypotype USNM 152435g′; 41–47, ventral, posterior, side, anterior, dorsal, and side views, ×2, ventral, posterior, anterior, dorsal, and side views; ×4, and dorsal view, ×6, of a complete specimen, hypotype USNM 152435h′; 48–51, interior, ×2, and interior, partial posterior, and posterior views, ×4, of a brachial valve showing the cardinalia, hypotype USNM 154422a; 52, interior of another brachial valve, ×2, hypotype USNM 154422c; 53, interior of a brachial valve, ×4, showing cardinalia, hypotype USNM 154422b; 54, posterior of a pedicle valve, showing the lateral plates along the sides of the delthyrium, ×4, hypotype USNM 154422d. [Bone Spring Formation, USNM 728f.]

PLATE 588.—Crurithyris.

PLATE 589

Crurithyris

Crurithyris tholiaphor, new species: 1, 2, Impression of the interior of a brachial valve and the replica prepared from it, ×1, paratype USNM 152447a; 3, impression of the pedicle valve showing elongate muscle scars, ×1, paratype USNM 152447b. [Word Formation (shaly beds above Willis Ranch Member), USNM 719e.]

4, Dorsal view of two immature complete specimens, ×1, paratypes USNM 152445a, b; 5–12, anterior, posterior, side, dorsal, and ventral views, ×1, and dorsal, anterior and side views, ×2, of a complete specimen, holotype USNM 152445k; 13, interior of a pedicle valve, ×1, paratype USNM 152445m; 14, 15, interior of a pedicle valve, ×1, ×2, showing cardinalia, paratype USNM 152445n; 16, ventral, posterior, side, anterior, and dorsal views of a young specimen, ×1, paratype USNM 152445d; 17, ventral, posterior, side, anterior, and dorsal views of another complete specimen, ×1, paratype USNM 152445f. [Word Formation (China Tank Member), USNM 706c.]

18, Interior, showing the cardinalia and descending branches of the spire, ×1, paratype USNM 152440b; 23, 24, ventral and oblique views of a complete spire, ×3, paratype USNM 152440a; 25, interior of a brachial valve, ×2, paratype USNM 152440c; 26, ventral, posterior, side, anterior, and dorsal views of a complete specimen, ×1, paratype USNM 152441a; 27–30, ventral, posterior, side, anterior, and dorsal views, ×1, and dorsal, side and anterior views, ×2, of a complete specimen, paratype USNM 152441b; 38, specimen with part of brachial valve removed to show spire, ×4, paratype USNM 154423. [Word Formation (Willis Ranch Member), USNM 706.]

19–21, Interior of the pedicle valve, ×1.5, and interior and tilted views, ×2, showing apical plate and muscle marks, paratype USNM 152449b; 22, interior of the brachial valve, ×2, showing cardinalia and descending lamellae of the spire, paratype USNM 152449c. [Cherry Canyon Formation (Getaway Member), USNM 728.]

31–37, Ventral, posterior, side, anterior, and dorsal views, ×1, and dorsal and anterior views, ×1.5, of a complete specimen, paratype USNM 152446a. [Word Formation (Willis Ranch Member), USNM 706e.]

Crurithyris tumibilis, new species: 39, Dorsal, anterior, side, posterior, and ventral views, ×1, of a complete specimen, paratype USNM 154424a; 40–43, dorsal, anterior, side, posterior, and ventral views, ×1, and anterior, side, and dorsal views, ×2, paratype USNM 154424b; 51, 52, partial posterior and interior views of a brachial valve, ×4, showing cardinalia, paratype USNM 154424c; 57, interior of another brachial valve, ×3, paratype USNM 154424e. [Neal Ranch Formation (bed 4), USNM 727e.]

44–48, Anterior, posterior, side, ventral, and dorsal views, ×1, and anterior, ventral, side, and dorsal views, ×2, holotype USNM 154425a; 49, 50, interior and tilted interior views of a brachial valve, ×4, showing descending branches of the spire, paratype USNM 154425c. [Neal Ranch Formation (bed 4), USNM 701d.]

53–56, Posterior, anterior, dorsal, and side views of a complete specimen, ×2, paratype USNM 154426a; 58, ventral oblique view of a broken specimen, showing part of the spire, ×3, paratype USNM 154426b. [Neal Ranch Formation (beds 12–14 of P. B. King), USNM 701k.]

PLATE 589.—Crurithyris.

PLATE 590

Crurithyris and Attenuatella

Crurithyris minutalis, new species: 1, 2, Dorsal view, ×1, and posterior, anterior, side, dorsal, and ventral views, ×2, paratype USNM 152417. [Road Canyon Formation, USNM 703d.]

3–8, Side, posterior, anterior, dorsal and ventral views, ×4, and dorsal view, ×1, of a complete specimen, paratype USNM 154427. [Road Canyon Formation, USNM 721j.]

9–12, Side, dorsal, posterior, and anterior views, ×10, paratype USNM 154428a; 13–16, posterior, anterior, side, and dorsal views of another complete specimen, ×10, holotype USNM 154428b; 17, ventral views of the two preceding specimens, ×1, USNM 154428b, a; 18, 19, interior and anterior views of a brachial valve with part of the spire, ×10, paratype USNM 154428j; 20, interior of another brachial valve with nearly complete spire on right side, ×10, paratype USNM 154428i; 21, 22, interior and posterior views of a brachial valve, ×10, showing the cardinalia, paratype USNM 154423d. [Road Canyon Formation (base), USNM 702c.]

Attenuatella texana Stehli: 23–26, Ventral, posterior, side, and interior views of a pedicle valve, ×2, hypotype USNM 152986d; 27–30, posterior, side, ventral, and interior views of another pedicle valve, ×2, hypotype USNM 152986c; 31, interior of the pedicle valve tilted to show the thick adductor ridge, ×2, hypotype USNM 152986h. [Bone Spring Formation, USNM 728f.]

Attenuatella attenuata (Cloud): 32–35, Ventral, side, and dorsal views of a steinkern of a complete specimen, and the replica prepared from it showing the cardinalia, ×3, hypotype USNM 154429b; 36–38, ventral, dorsal, and side views of another steinkern, ×3, hypotype USNM 154429a; 39, dorsal view of a steinkern showing the form of the brachial valve, ×3, hypotype USNM 154429c. [Permian (Word equivalent), USNM 814.]

Crurithyris tumibilis, new species: 40–45, Ventral, anterior, side, posterior, and dorsal views, ×1, and posterior, side, dorsal, anterior and ventral views, ×2, of a complete specimen, paratype USNM 152406z; 46, ventral, anterior, side, posterior, and dorsal views of a complete specimen, ×1, paratype USNM 152406b′; 47, dorsal, anterior, and side views of a young specimen, ×1, paratype USNM 152406n; 48, dorsal, anterior and side views, of another young specimen, ×1, paratype USNM 152406s. [Neal Ranch Formation (beds 12–14 of P. B. King), USNM 701k.]

49–52, Partial posterior, interior, side, and anterior views of a brachial valve preserving the complete spire, ×6, paratype USNM 152402. [Neal Ranch Formation (bed 4), USNM 701d.]

PLATE 590.—Crurithyris and Attenuatella.

PLATE 591

Gypospirifer

[All ×1]

Gypospirifer gryphus, new species: 1–5, Dorsal, ventral, posterior, side, and anterior views of adult shell, holotype USNM 154615a. [Graham Formation (Wayland Shale Member), USNM 728x.]

Gypospirifer nelsoni, new species: 6–9, Dorsal, ventral, anterior, and posterior views of adult shell, holotype USNM 111919a. [Hueco Formation (near base), USNM 728y.]

PLATE 591.—Gypospirifer.

PLATE 592

Gypospirifer and Neospirifer

Gypospirifer condor (d’Orbigny): 1–5, Dorsal, ventral, posterior, anterior, and side views, ×1, adult shell hypotype USNM 154616a; 6–10, dorsal, ventral, posterior, anterior, and side views, ×1, adult shell, hypotype USNM 154616b. [Copacabana Formation, USNM 728z.]

Neospirifer amphigyus, new species: 11, Interior view of brachial valve with part of spire, buccal plate displaced from its median position, ×2, paratype USNM 154597. [Word Formation (Appel Ranch Member), USNM 716v.]

PLATE 592.—Gypospirifer and Neospirifer.

PLATE 593

Neospirifer and Gypospirifer

[All ×1]

Neospirifer amphigyus, new species: 1, 2, Exterior and interior views of large pedicle valve, paratype:USNM 152894x; 3, 4, exterior and interior views of alate brachial valve, paratype USNM 154595a; 6–10, dorsal, ventral, side, posterior, and anterior views, juvenile paratype USNM 152894b; 11–15, dorsal, posterior, ventral, anterior, and side views, juvenile paratype USNM 152894e. [Word Formation (China Tank Member), USNM 706c.]

5, Exterior view of asymmetrical pedicle valve, paratype USNM 152893c. [Word Formation (Willis Ranch Member), USNM 706.]

Gypospirifer anancites, new species: 16–20, Dorsal, ventral, anterior, side, and posterior views, adult holotype USNM 152895c; 22–25, ventral, dorsal, posterior, and side views, adult paratype USNM 152895f. [Hueco Canyon Formation, USNM 499b.]

21, Side view into right half of shell with primary lamella and spire, paratype USNM 154598. [Hueco Canyon Formation, USNM 725z.]

PLATE 593.—Neospirifer and Gypospirifer.

PLATE 594

Neospirifer

[All ×1]

Neospirifer amphigyus, new species: 1–5, Dorsal, ventral, anterior, side, and posterior views, adult holotype USNM 152894y; 7, exterior view of adult pedicle valve, paratype USNM 152894i; 8, 9, exterior and interior views of alate pedicle valve, paratype USNM 154596c; 10, 11, interior and exterior views of brachial valve, paratype USNM 154596b. [Word Formation (China Tank Member), USNM 706c.]

6, Exterior view of adult pedicle valve, paratype USNM 152893e. [Word Formation (Willis Ranch Member), USNM 706.]

PLATE 594.—Neospirifer.

PLATE 595

Neospirifer

[All ×1]

Neospirifer apothescelus, new species: 1–4, Ventral, dorsal, side, and anterior views of large adult partly restored with plaster, holotype USNM 154599a; 5–7, dorsal, ventral, and anterior views of large adult partly restored with plaster, paratype USNM 154599b. [Neal Ranch Formation, USNM 727e.]

8–9, Exterior and interior views of brachial valve, paratype USNM 152900d; 10–14, dorsal, ventral, posterior side, and anterior views, juvenile paratype USNM 152900c. [Neal Ranch Formation, USNM 701.]

15–19, Dorsal, ventral, posterior, side, and anterior views, young adult paratype USNM 154600a. [Neal Ranch Formation, USNM 722x.]

20, Dorsal view, broken paratype USNM 154601a. [Neal Ranch Formation, USNM 721g.]

PLATE 595.—Neospirifer.

PLATE 596

Neospirifer

[All ×1]

Neospirifer bakeri bakeri R. E. King [all hypotypes]: 1–4, Dorsal, ventral, side, and posterior views of juvenile shell, USNM 152904e; 5–10, dorsal, ventral, side, dorsolateral, posterior, and anterior views of juvenile shell, USNM 152904g; 11–15, dorsal, ventral, side, posterior, and anterior views of juvenile shell, USNM 152904i; 16–19, dorsal, ventral, posterior, and anterior views of alate juvenile shell, USNM 154613a; 20–25, dorsal, ventral, side, dorsolateral, posterior, and anterior views of juvenile shell, USNM 152904–l; 26–29, dorsal, ventral, posterior, and anterior views of alate juvenile shell, USNM 154613b; 30–32, dorsal, posterior, and anterior views of alate young adult shell, USNM 152904q; 33–36, dorsal, ventral, posterior, and anterior views of young adult shell, USNM 154613c; 37–40, dorsal, ventral, posterior, and anterior views of slightly crushed adult shell, USNM 152904r; 41–45, dorsal, ventral, posterior, anterior, and side views of large adult shell, USNM 154613d; 46, interior view of pedicle valve, USNM 154613e; 47, interior view of brachial valve, USNM 154613f. [Road Canyon Formation, USNM 707e.]

PLATE 596.—Neospirifer.

PLATE 597

Neospirifer

Neospirifer bakeri bakeri R. E. King [all hypotypes]: 1–5, Dorsal, ventral, posterior, anterior, and side views of adult shell, ×1, USNM 152904za; 6, interior view of fragmentary pedicle valve, ×1, paratype USNM 154613g; 7, interior view of fragmentary pedicle valve, ×1, paratype USNM 154613h; 8, dorsal view of shell broken to show parts of spire, buccal plate near middle, ×1, paratype USNM 154613i; 9–11, ventral, dorsal, and side views of buccal plate, ×3, USNM 154613j; 12–14, ventral, side and dorsal views of buccal plate, ×3, USNM 154613k. [Road Canyon Formation, USNM 707e.]

PLATE 597.—Neospirifer.

PLATE 598

Neospirifer

[All ×1]

Neospirifer bakeri columbarius, new subspecies: 1–5, Dorsal, ventral, side, posterior, and anterior views, juvenile paratype USNM 152905e; 6–10, dorsal, ventral, side, posterior, and anterior views, juvenile paratype USNM 152905g; 11–15, dorsal, ventral, posterior, side, and anterior views, young adult paratype USNM 152905h; 16–20, dorsal, ventral, anterior, side, and posterior views of adult paratype with attached coral, USNM 154602a; 21, interior view of posterior part of pedicle valve, paratype USNM 154602b; 22–26, dorsal, ventral, posterior, side, and anterior views, large adult paratype USNM 152905m. [Road Canyon Formation, USNM 703d.]

PLATE 598.—Neospirifer.

PLATE 599

Neospirifer

Neospirifer bakeri columbarius, new subspecies: 1–5, Dorsal, ventral, side, posterior, and anterior views of strongly ribbed juvenile, ×1, paratype USNM 154603a; 6, 7, dorsal and ventral views of alate young adult shell, ×1, paratype USNM 154603b. [Road Canyon Formation, USNM 724a.]

8–12, Dorsal, ventral, posterior, anterior, and side views, ×1, adult holotype USNM 152905p; 13, side view of broken shell with part of spire and buccal plate, ×2, paratype USNM 154602d; 14, interior view of articulated hinge and cardinal region, fragment, ×1, paratype USNM 154602c. [Road Canyon Formation, USNM 703d.]

PLATE 599.—Neospirifer.

PLATE 600

Neospirifer

Neospirifer bakeri columbarius, new subspecies: 1, 2, Dorsal views of shell broken to show spiralium and buccal plate in place between spires, ×1, and ×2.5, paratype USNM 154602f.

3–5, Side, ventral, and dorsal views of buccal plate, ×3, 154602d, paratype USNM 154602e; 6, interior view of brachial valve, ×1, paratype USNM 154602g; 7–9, dorsal, ventral, and posterior views of adult shell with attached coral, ×1, paratype USNM 154602h; 10, interior view of posterior part of brachial valve, ×1, paratype USNM 154602i. [Road Canyon Formation, USNM 703d.]

11, Interior view of strongly alate pedicle valve, ×1, paratype USNM 154603c. [Road Canyon Formation, USNM 724a.]

PLATE 600.—Neospirifer.

PLATE 601

Neospirifer and Gypospirifer

[All ×1]

Neospirifer bakeri bakeri R. E. King: 1–5, Dorsal, ventral, anterior, posterior, and side views, ×1, holotype illustrated by King (1931, pl. 37: figs. 6a–c), YPM 12500. [“Word Formation, lower limestone” ═ Road Canyon Formation, YPM 46.]

Gypospirifer infraplicus (R. E. King): 6–10, Dorsal, ventral, side, posterior, and anterior views of cotype illustrated by King (1931, pl. 36: figs. 2a–c), YPM 12402. [Bone Spring Formation, Victorio Peak Member, YPM 499.]

11–14, Dorsal, side, posterior, and cardinal views of brachial valve illustrated by King (1931, pl. 36, figs. 4a–c), T10043b, herein designated lectotype. [Leonard Formation, UT locality Tg (R. E. King, 1931).]

15–18, Ventral, side, posterior, and cardinal views of cotype illustrated by King (1931, pl. 36: figs. 3a–c) T10043a. [Leonard Formation, UT locality Tg (R. E. King, 1931).]

PLATE 601.—Neospirifer and Gypospirifer.

PLATE 602

Neospirifer and Gypospirifer

Neospirifer formulosus, new species: 1–5, Dorsal, ventral, posterior, side, and anterior views, ×1, juvenile paratype USNM 152907. [Road Canyon Formation, USNM 724c.]

6, Exterior view of juvenile pedicle valve, ×1, paratype USNM 152908a; 7, exterior view of juvenile brachial valve, ×1, paratype USNM 152908b. [Road Canyon Formation, USNM 720d.]

8–9, Ventral and posterior views, ×1, adult holotype USNM 152906f; 10, dorsal view, ×1, young adult paratype USNM 152906g; 11–12, dorsal and ventral views, ×1, adult paratype USNM 152906d; 13, interior view of pedicle valve, ×1, paratype USNM 152906e; 14, interior view of brachial valve, ×2, paratype USNM 152906j. [Road Canyon Formation, USNM 723a.]

Gypospirifer infraplicus (R. E. King) [all hypotypes]: 15, Exterior view slightly more than half of right side of pedicle valve, ×1, USNM 152911g; 16, exterior view of brachial valve, ×1, USNM 152911f; 17–18, exterior and interior views of complete brachial valve, ×1, USNM 152911e; 19, exterior view, small fragmentary pedicle valve, ×1, USNM 152911h. [Skinner Ranch Formation (Decie Ranch Member), USNM 705a.]

PLATE 602.—Neospirifer and Gypospirifer.

PLATE 603

Neospirifer

Neospirifer mansuetus, new species: 1–6, Dorsal views, ×1, and ×2, ventral, anterior, posterior, and side views, ×2, nepionic paratype USNM 154606o; 17–21, dorsal, ventral, posterior, side, and anterior views, ×1, adult paratype USNM 152913c; 22, interior view of articulated posterior median fragment, ×2, showing cardinalia, paratype USNM 154606b; 28, interior view of brachial valve, ×1, paratype USNM 154606c; 29, interior view of brachial valve, ×1, paratype USNM 154606d. [Cathedral Mountain Formation (base), USNM 702.]

7–11, Dorsal, ventral, posterior, anterior, and side views, ×1, juvenile paratype USNM 152912a; 12–16, dorsal, ventral, posterior, side, and anterior views, ×1, juvenile paratype USNM 152912d; 23–26, dorsal, ventral, anterior, and side views, ×1, adult paratype USNM 152912g. [Cathedral Mountain Formation (base) USNM 702un].

27, Ventral view of broken shell, ×1, paratype USNM 154607a. [Cathedral Mountain Formation (base), USNM 702 low.]

PLATE 603.—Neospirifer.

PLATE 604

Neospirifer

Neospirifer mansuetus, new species: 1–5, Dorsal, ventral, side, posterior, and anterior views, ×1, juvenile paratype USNM 154615a; 6–10, dorsal, ventral, side, anterior, and posterior views, ×1, juvenile paratype USNM 154615b; 11, interior view of brachial valve, ×2, paratype USNM 154615c; 12–15, dorsal, ventral, side, and posterior views, ×1, adult paratype USNM 154615d; 16–20, dorsal, ventral, anterior, side, and posterior views, ×1, adult paratype USNM 154615e. [Cathedral Mountain Formation, USNM 702a]

21–24, Dorsal, posterior, anterior, and side views, ×1, large adult holotype USNM 152913e. [Cathedral Mountain Formation (base), USNM 702.]

25–27, Ventral, dorsal, and side views of buccal plate, ×3, paratype USNM 152912j. [Cathedral Mountain Formation (base), USNM 702un.]

PLATE 604.—Neospirifer.

PLATE 605

Neospirifer

Neospirifer mansuetus, new species: 1–5, Dorsal, ventral, posterior, side, and anterior views, ×1, large adult paratype USNM 152913d; 6, interior view of broken pedicle valve, ×1, paratype USNM 154606e. [Cathedral Mountain Formation (base), USNM 702.]

7–9, Ventral, side, and dorsal views of buccal plate, ×2, paratype USNM 154607b. [Cathedral Mountain Formation (base), USNM 702-low.]

Neospirifer neali, new species: 10–14, Dorsal, ventral, anterior, side, and posterior views, ×1, young adult paratype USNM 152915c. [Hess Formation (Taylor Ranch Member), USNM 702d.]

15–17, Ventral, dorsal, and side views of buccal plate, ×2, paratype USNM 154608a. [Bone Spring Formation, AMNH 591.]

PLATE 605.—Neospirifer.

PLATE 606

Neospirifer

[All ×1]

Neospirifer neali, new species: 1–5, Dorsal, ventral, posterior, side and anterior views of adult, holotype USNM 152915b; 7–10, dorsal, ventral, side and posterior views of large adult, paratype USNM 152915a. [Hess Formation (Taylor Ranch Member), USNM 702d.]

6, Posterior view of adult, paratype USNM 154508b. [Bone Spring Formation, AMNH 591.]

PLATE 606.—Neospirifer.

PLATE 607

Neospirifer

[All ×1]

Neospirifer notialis, new species: 1–5, Dorsal, ventral, side, posterior, and anterior views, young adult paratype USNM 152910a; 6–9, dorsal, ventral, posterior, and anterior views, large adult paratype USNM 152910f: 10–14, dorsal, ventral, posterior, side, and anterior views, adult holotype USNM 152910b, [Hess Formation (Taylor Ranch Member), USNM 702e.]

PLATE 607.—Neospirifer.

PLATE 608

Neospirifer

[All ×1]

Neospirifer notialis, new species: 1–5, Dorsal, ventral, posterior, side, and anterior views of adult, paratype USNM 154604a. [Hess Formation (Taylor Ranch Member), USNM 702d.]

6–9, Dorsal, ventral, side, and posterior views of adult, paratype USNM 152910g; 10–11, dorsal and posterior views of adult, paratype USNM 152910h; 12, interior view of posterior part of pedicle valve, paratype USNM 152910i; 13, interior view of median part of pedicle valve, paratype USNM 1529l0j, [Hess Formation (Taylor Ranch Member), USNM 702e.]

PLATE 608.—Neospirifer.

PLATE 609

Neospirifer

[All ×1]

Neospirifer placidus, new species: 1–4, Dorsal, ventral, side, and anterior views of juvenile, paratype USNM 153276–1; 5–8, dorsal, ventral, side, and anterior views of juvenile, paratype USNM 153276m; 9–12, dorsal, ventral, side, and anterior views of juvenile, paratype USNM 153276q; 13–16, dorsal, ventral, side, and anterior views of juvenile, paratype USNM 153276n; 17–20, dorsal, ventral, anterior, and side views of juvenile, paratype USNM 153276g; 21–25, dorsal, ventral, side, anterior, and posterior views of paratype, somewhat encrusted and deformed adult, USNM 153276o; 26–29, dorsal, ventral, side, and anterior views of adult with pedicle valve encrusted, holotype USNM 153276j. [Neal Ranch Formation, USNM 727e.]

Neospirifer thescelus, new species: 30–34, Dorsal, ventral, side, posterior, and anterior views of juvenile, paratype USNM 152916–1; 35–39, dorsal, ventral, side, anterior, and posterior views of juvenile, paratype USNM 152916o; 40–44, dorsal, ventral, side, posterodorsal, and anterior views of young adult, paratype USNM 152916s; 45–48, dorsal, ventral, side, and anterior views of young adult, paratype USNM 152916u. [Road Canyon Formation, USNM 702c.]

PLATE 609.—Neospirifer.

PLATE 610

Neospirifer

[All ×1]

Neospirifer thescelus, new species: 1–5, Dorsal, ventral, side, posterior, and anterior views of juvenile, paratype USNM 154610a; 6–10, dorsal, ventral, side, posterior, and anterior views of juvenile, paratype USNM 154610b; 11–15, dorsal, ventral, side, anterior, and posterior views of juvenile, paratype USNM 154610c: 16–20, dorsal, ventral, side, anterior, and posterior views of juvenile, paratype USNM 154610d; 21–25, dorsal, ventral, side, anterior, and posterior views of young adult encrusted with richthofeniid spat, paratype USNM 154610e; 26–29, dorsal, ventral, side, and posterior views of adult paratype USNM 154610f; 35–38, ventral, dorsal, side, and anterior views of asymmetrical adult, paratype USNM 154610g. [Road Canyon Formation, USNM 702c.]

30–34, Dorsal, ventral, posterodorsal, anterior, and side views of adult with left side broken and healed, ×1, paratype USNM 154611a. [Road Canyon Formation, USNM 721o.]

PLATE 610.—Neospirifer.

PLATE 611

Neospirifer

Neospirifer thescelus, new species: 1–2, Dorsal and posterior views of large adult with epifaunal richthofeniids, ×1, paratype USNM 152916a; 6, interior view of cardinal region of brachial valve, ×2, paratype USNM 154610i; 7, interior view of cardinal region of pedicle valve, ×1, paratype USNM 154610h, 8–9, right and left side views of shell broken on right to show tooth in socket and apposition of valves along hinge, ×1, paratype USNM 154610j. [Road Canyon Formation, USNM 702c.]

3–5, Ventral, side, and anterior views of large adult, ×1, paratype USNM 152918a; 10–12, ventral, dorsal, and side views, ×3, buccal plate, USNM 152918b. [Road Canyon Formation, USNM 721y.]

PLATE 611.—Neospirifer.

PLATE 612

Neospirifer

[All ×1]

Neospirifer thescelus, new species: 1–5, Dorsal, ventral, posterior, side, and anterior views of adult, paratype USNM 152917b. [Road Canyon Formation, USNM 719x.]

6–10, Dorsal, ventral, posterior, side, and anterior views of adult, holotype USNM 152916y. [Road Canyon Formation, USNM 702c.]

11–12, Ventral and dorsal views of adult broken to show left spire and buccal plate (not in place), paratype USNM 154612a. [Road Canyon Formation, USNM 703a.]

PLATE 612.—Neospirifer.

PLATE 613

Cartorhium

Cartorhium chelomatum, new species: 1–5, Dorsal, ventral, side, posterior, and anterior (ventral up) views, ×1, juvenile paratype USNM 151840b; 6–10, dorsal, ventral, side, posterior, and anterior views, ×1, juvenile paratype USNM 151840f; 11–14, dorsal, ventral, side, and anterior views, ×1, juvenile paratype USNM 151839a; 15–19, dorsal, ventral, side, posterior, and anterior views, ×1, young adult paratype USNM 151840h; 20–21, interior and exterior views of pedicle valve, ×1, paratype USNM 151839b; 22–23, interior and exterior views of brachial valve, ×1, paratype USNM 151839c; 24–25, interior and exterior views of brachial valve, ×1, paratype USNM 151839d; 26–28, dorsal, ventral, and side views of buccal plate, ×2, paratype USNM 151839e; 29–33, dorsal, ventral, side, anterior, and posterior views, ×1, adult holotype USNM 151840m. [Word Formation, lens between Willis Ranch and Appel Ranch members, USNM 706b.]

34, 35, Exterior and interior views of a pedicle valve encrusted by strophalosiid spat, ×1, paratype USNM 154617a. [Word Formation (Appel Ranch Member), USNM 719z.]

Cartorhium coristum, new species: 36–37, External and internal views of brachial valve with articulated umbonal part of pedicle valve, ×1, paratype USNM 154618a; 38–39, exterior and interior views of brachial valve, ×1, paratype USNM 154618b. [Cathedral Mountain Formation, USNM 714w.]

PLATE 613.—Cartorhium.

PLATE 614

Cartorhium

[All ×1]

Cartorhium coristum, new species: 1–5, Dorsal, ventral, posterior, side, and anterior views of young adult, paratype USNM 152919–1; 11–15, dorsal, side, ventral, anterior, and posterior views of adult, paratype USNM 152919n; 16–20, dorsal, ventral, side, anterior, and posterior views of adult, paratype USNM 152919o. [Cathedral Mountain Formation (Wedin Member), USNM 714w.]

6–10, Dorsal, ventral, posterior, side, and anterior views of young adult, paratype USNM 152921a. [Cathedral Mountain Formation, USNM 727p.]

21–25, Dorsal, ventral, posterior, anterior, and side views of adult, holotype USNM 152920a. [Cathedral Mountain Formation, USNM 708.]

PLATE 614.—Cartorhium.

PLATE 615

Cartorhium

Cartorhium latum (R. E. King) [all hypotypes]: 1–5, Dorsal, ventral, side, posterior, and anterior views, ×1, juvenile shell USNM 152922i; 6–10, dorsal, ventral, anterior, posterior, and side views, ×1, juvenile shell USNM 152922–1; 11–15, dorsal, ventral, anterior, posterior, and side views, ×1, juvenile shell USNM 152922o; 29–33, dorsal, ventral, posterior, side, and anterior views, ×1, adult shell USNM 152922q. [Cathedral Mountain Formation (base), USNM 702a.]

16–20, Dorsal, ventral, side, posterior, and anterior views, ×1, young adult shell USNM 152926e; 23, interior view of broken brachial valve, ×2, USNM 152926f; 24–28, dorsal, ventral, posterior, side, and anterior views, ×1, adult shell USNM 152926d, pedicle valve encrusted by bryozoa. [Cathedral Mountain Formation (base), USNM 702.]

21–22, Dorsal and side views, ×1, young adult shell USNM 152923b. [Cathedral Mountain Formation (base), USNM 702un.]

PLATE 615.—Cartorhium.

PLATE 616

Cartorhium

Cartorhium latum (R. E. King) [all hypotypes]: 1–3, Ventral, dorsal, and side views of buccal plate, ×3, USNM 152926g; 18–20, ventral, dorsal, and side views of buccal plate, ×3, USNM 152926h; 21–23, ventral, dorsal, and side views of buccal plate, ×3, USNM 152926i. [Cathedral Mountain Formation (base), USNM 702.]

4–6, Ventral, dorsal, and side views of buccal plate, ×3, USNM 152925c. [Cathedral Mountain Formation, USNM 703a^1.]

7–8, Exterior and interior views of pedicle valve, ×1, USNM 152923c; 9–10, Exterior and interior views of broken pedicle valve encrusted by bryozoa, −1, USNM 152923d. [Cathedral Mountain Formation (base), USNM 702un.]

11–12, Exterior and interior views of broken brachial valve, ×1, USNM 152922r. [Cathedral Mountain Formation (base), USNM 702a.]

13–17, Dorsal, ventral, posterior, side, and anterior views of large adult shell, ×1, USNM 152924a. [Cathedral Mountain Formation (base), USNM 703b.]

PLATE 616.—Cartorhium.

PLATE 617

Cartorhium

Cartorhium orbiculatum, new species: 1–2, Dorsal and ventral views, ×1, juvenile paratype USNM 152885j; 3–4, exterior and interior views of juvenile pedicle valve, ×1, paratype USNM 152885m; 5–6, exterior and interior views of adult brachial valve, ×1, paratype USNM 152885q; 17–20, dorsal, ventral, anterior, and posterior views of compressed adult, ×1, paratype USNM 152885p. [Word Formation (Appel Ranch Member), USNM 706d.]

7–11, Dorsal, ventral, posterior, anterior, and side views, ×1, adult paratype USNM 152886c; 12–16, dorsal, ventral, side, anterior, and posterior views of adult, ×1, holotype USNM 152886b. [Word Formation, (Appel Ranch Member), USNM 714o.]

Cartorhium retusum, new species: 21–22, Exterior and interior views of emarginate brachial valve, ×1, paratype USNM 152929r; 23–24, Ventral and side views of buccal plate, ×3, paratype USNM 152929V. [Cherry Canyon Formation (Getaway Member), USNM 728.]

25–26, Exterior and interior views of large adult brachial valve, ×1, paratype USNM 152930b. [Word Formation (Appel Ranch Member), USNM 719z.]

PLATE 617.—Cartorhium.

PLATE 618

Cartorhium

[All ×1]

Cartorhium retusum, new species: 1–5, Dorsal, ventral, side, posterior, and anterior views, juvenile paratype USNM 152929d; 6–10, dorsal, ventral, side, posterior, and anterior views, juvenile paratype USNM 152929h; 11–15, dorsal, ventral, side, anterior, and posterior views, juvenile paratype USNM 152929k; 16–17, exterior and interior views of young adult pedicle valve, paratype USNM 152929p; 18–19, exterior and interior views of broken adult pedicle valve, holotype USNM 152929w; 20–21, exterior and interior views of adult brachial valve, paratype USNM 152929x; 22–23, exterior and interior views of adult pedicle valve, paratype USNM 152929y; 26–27, exterior and interior views of emarginate brachial valve, paratype USNM 152929o; 28–29, exterior and interior views of encrusted pedicle valve, probably gerontic, paratype USNM 152929u. [Cherry Canyon Formation (Getaway Member), USNM 728.]

24–25, Exterior and interior views of large adult pedicle valve, paratype USNM 154620a. [Word Formation (Appel Ranch Member), USNM 715i.]

PLATE 618.—Cartorhium.

PLATE 619

Cartorhium

[All ×1]

Cartorhium vidriense, new species: 1–5, Dorsal, ventral, anterior, side, and posterior views, adult holotype USNM 154626a; 8–9, exterior and interior views of adult pedicle valve, paratype USNM 154626b. [Word Formation (China Tank Member), USNM 706c.]

6–7, Exterior and interior views of adult brachial valve, paratype USNM 154627. [Word Formation (Willis Ranch Member), USNM 706.]

Cartorhium mexicanum (Shumard) [all hypotypes]: 10–14, Dorsal, ventral, posterior, anterior, and side views of adult shell partly restored with plaster, USNM 152927e; 15–19, dorsal, ventral, anterior, side, and posterior views of adult shell, USNM 152927c; 20, side view adult shell, USNM 152927b. [Capitan Formation, AMNH 475].

PLATE 619.—Cartorhium.

PLATE 620

Cartorhium.

[All ×1]

Cartorhium zoyei, new species: 1–5, Dorsal, ventral, posterior, side, and anterior (pedicle valve up) views, juvenile paratype USNM 151851a; 6–10, Dorsal, ventral, anterior, and side views, young adult paratype USNM 151851b; 11–15, Dorsal, ventral, posterior, anterior, and side views, adult paratype USNM 151851c; 16–20, Dorsal, side, ventral, anterior, and posterior views, adult paratype USNM 151851d. [Skinner Ranch Formation (Decie Ranch Member), USNM 714t.]

21–25, Dorsal, ventral, posterior, side, and anterior views, large adult holotype USNM 152932b. [Skinner Ranch Formation (Decie Ranch Member), USNM 727u.]

PLATE 620.—Cartorhium.

PLATE 621

Lepidospirifer

Lepidospirifer angulatus Cooper and Grant: 1–5, Dorsal, ventral, side, anterior, and posterior views, ×1, young adult hypotype USNM 154629a. [Cathedral Mountain Formation (base), USNM 702a.]

6–10, Dorsal, ventral, anterior, posterior, and side views, ×1, adult holotype USNM 152940a; 14, interior view of adult brachial valve, ×1, hypotype USNM 152940b. [Cathedral Mountain Formation (base), USNM 702.]

11–12, Interior views of adult pedicle valve, ×1, hypotype USNM 151942a. [Cathedral Mountain Formation (base), USNM 702un.]

13, Interior view of brachial valve, ×2, hypotype USNM 154630a. [Cathedral Mountain Formation, USNM 703b.]

Lepidospirifer costellus (R. E. King) [all hypotypes]: 15–19, Dorsal, ventral, anterior, posterior, and side views of adult shell, ×1, USNM 151832b; 20–21, dorsal and posterior views of thin adult shell, ×1, USNM 151832a. [Cathedral Mountain Formation (base), USNM 703b.]

PLATE 621.—Lepidospirifer.

PLATE 622

Lepidospirifer

Lepidospirifer inferus, new species: 1–3, Dorsal, ventral, and posterior views, ×1, adult holotype USNM 154632. [Cathedral Mountain Formation, USNM 726o.]

4, Interior view of brachial valve, ×1, paratype USNM 151846p; 5–6, interior views of pedicle valve, ×1, paratype USNM 151846t; 9, exterior view of ornament of fragmentary pedicle valve, ×4, paratype USNM 151846u. [Cathedral Mountain Formation (base), USNM 702b.]

Lepidospirifer angulatus, Cooper and Grant: 7, Exterior view of brachial valve magnified to show ornament, ×4, paratype USNM 154630b. [Cathedral Mountain Formation, USNM 703b.]

10, Exterior view of fragmentary pedicle valve, ×4, magnified to show ornament, paratype USNM 152941i. [Cathedral Mountain Formation, USNM 703a^1.]

Lepidospirifer demissus, new species: 8, Exterior view of sulcus of pedicle valve magnified to show ornament, ×4, paratype USNM 154631a. [Cathedral Mountain Formation, USNM 721u.]

PLATE 622.—Lepidospirifer.

PLATE 623

Lepidospirifer

Lepidospirifer demissus, new species: 1–5, Dorsal, ventral, anterior, posterior, and side views, ×1, juvenile paratype USNM 151821a; 6–10, dorsal, ventral, posterior, side, and anterior views, ×1, juvenile paratype USNM 151821b; 11–12, interior views of pedicle valve, ×1, paratype USNM 151821c; 13, 14, interior views of brachial valve, ×1, paratype USNM 151821d; 16, side oblique view of adult shell broken to show displaced spire, ×1, paratype USNM l51821q; 27–29, ventral, side, and dorsal views of buccal plate, ×2, USNM 151821f. [Cathedral Mountain Formation (base), USNM 702.]

15, Interior view of pedicle valve with articulated fragment of brachial valve, ×1, paratype USNM 151827d; 17–21, dorsal, ventral, posterior, anterior, and side views, ×1, adult paratype USNM 151827c; 22–26, dorsal, ventral, posterior, side, and anterior views, ×1, large adult holotype USNM 151827b. [Cathedral Mountain Formation (base), USNM 702un.]

PLATE 623.—Lepidospirifer.

PLATE 624

Cartorhium, Lepidospirifer, and Neospirifer

Cartorhium latum (R. E. King): 1–5, Dorsal, ventral, side, posterior, and anterior views, ×1, holotype (illustrated by King, 1931, pl. 37: figs. 7a-d) YPM 12504. [Leonard Formation, R. E. King 123 (King, 1931) ═ Cathedral Mountain Formation, USNM 711q.]

6–10, Dorsal, ventral, side, anterior, and posterior views, ×1, of specimen illustrated by King (1931, pl. 38: figs, 1a-c), YPM 12505. [Leonard Formation, R. E. King 126 (King, 1931) ═ Cathedral Mountain Formation.]

Lepidospirifer costellus (R. E. King): 11–16, Dorsal, ventral, anterior, side, and posterior views, ×1, and exterior view, ×4, showing detail of ornamentation, holotype (illustrated by King, 1931, pl. 37: figs. 3a-d) YPM 12437. [Leonard Formation, R. E. King 174 (King, 1931) ═ Cathedral Mountain Formation.]

Neospirifer huecoensis (R. E. King): 17–21, Dorsal, ventral, anterior, side, and posterior views, ×1, holotype (illustrated by King, 1931, pl. 38: figs. 2a-c). YPM 12441. [Gym Formation, R. E. King 389 (King, 1931) ═ Hueco Formation.]

PLATE 624.—Cartorhium, Lepidospirifer, and Neospirifer.

PLATE 625

Spiriferinaella

Spiriferinaella limata, new species: 1–2, Dorsal and ventral views of juvenile with left side broken off, ×1, paratype USNM 152943b; 3–4, exterior and interior views of juvenile brachial valve, ×1, paratype USNM 152943c; 5–6, exterior and interior views of adult brachial valve, ×1, paratype USNM 152943f; 7–8, exterior and interior views of broken brachial valve, ×1, holotype USNM 152943e; 9, interior view of fragment of thickened pedicle valve, ×2, paratype USNM 152943g; 10, interior view of fragment of pedicle valve, ×2, paratype USNM 152943d. [Word Formation (China Tank Member, USNM 706c.]

Spiriferinaella scalpata, new species: 11–14, Internal and dorsal and ventral external views, ×1, shown articulated and disarticulated, adult holotype USNM 152947a; 27, interior view, ×1, fragment of pedicle valve, paratype USNM 152947b. [Word Formation (lens between Willis Ranch and Appel Ranch members), USNM 706b.]

15–18, Posterior and ventral views, ×1, ×3, young juvenile paratype USNM 152946a; 19–20, dorsal and ventral views, ×1, young adult paratype USNM 152946b. [Word Formation (Appel Ranch Member), USNM 706d.]

21–23, Interior and exterior views, ×1, and interior cardinal view, ×3, of alate brachial valve, paratype USNM 152945b; 24–26, interior and exterior views, ×1, and detailed exterior view, ×4, of fragment of pedicle valve, paratype USNM 152945c; 28, posterior view of pedicle valve with delthyrial cover, ×3, paratype USNM 152945d. [Word Formation (Appel Ranch Member), USNM 715i.]

PLATE 625.—Spiriferinaella.

PLATE 626

Spiriferinaella, Eridmatus, and Spiriferella

Spiriferinaella medialis, new species: 1–5, Dorsal, ventral, anterior, posterior, and side views, ×1, holotype USNM 152944a. [Cherry Canyon Formation (Getaway Member), USNM 728.]

Spiriferinaella species undetermined: 6, 7, Dorsal and posterior views of fragmentary shell, ×1, USNM 154549. [Word Formation, USNM 731u.]

8, 9, ventral and posterior views of fragmentary shell, ×1, USNM 154550. [Word Formation, USNM 731m.]

Eridmatus marathonensis, new species: 10–14, Dorsal, ventral, side, anterior, and posterior views, ×1, juvenile paratype USNM 152977b; 15–19, dorsal, ventral, side, posterior, and anterior views, ×1, exfoliated holotype USNM 152977a; 20, polished transverse section cut about midlength to show form of spire, ×1, paratype USNM 152977c. [Gaptank Formation, USNM 701v.]

Spiriferella calcarata, new species: 21, Ventral view of juvenile pedicle valve, ×1, paratype USNM 152948j; 22, Ventral view of juvenile pedicle valve, ×1, paratype USNM 152948–1; 23–24, dorsal and ventral views, ×1, juvenile paratype USNM 152948r; 25–26, exterior and interior views of juvenile brachial valve, ×1, paratype USNM 152948u; 27, anteroventral view of shell broken to show spiralium, ×1, paratype USNM 152948q; 28, ventral view, adult pedicle valve, ×1, paratype USNM 152948m; 29–30, interior and exterior views of young adult brachial valve, ×1, paratype USNM 152948v; 31–33, exterior and interior views, ×1, and detail of exterior ornament, ×4, of adult brachial valve, paratype USNM 152948t; 34–36, dorsal and ventral views, ×1, and detail of ornament of pedicle valve, ×4, of adult holotype USNM 152948s. [Word Formation (Willis Ranch Member), USNM 706e.]

PLATE 626.—Spiriferinaella, Eridmatus, and Spiriferella.

PLATE 627

Spiriferella

[All ×1]

Spiriferella clypeata, new species: 1, 2, Dorsal and ventral views of juvenile paratype USNM 152950d; 3, 4, exterior and interior views of juvenile brachial valve, paratype USNM 152950r; 5, interior view of brachial valve, paratype USNM 152950p; 6, 7, exterior and interior views of young adult pedicle valve, paratype USNM 152950s; 8, 9, exterior and interior views of young adult pedicle valve, paratype USNM 152950t; 12–13, exterior and interior views of young adult brachial valve, paratype USNM 152950q; 14, dorsal view of extensively bored adult, paratype USNM 152950m; 15, 16, ventral and side views of adult, paratype USNM 152950n; 19–22, dorsal, side, ventral, and posterior views of slightly crushed holotype USNM 152950o. [Word Formation (Appel Ranch Member), USNM 715i.]

10, 11, Exterior and interior views of large pedicle valve, paratype USNM 154551a. [Word Formation (Appel Ranch Member), USNM 719z.]

17, 18, Dorsal and ventral views of large adult, paratype USNM 154552a (for enlargement see Plate 628: figure 37). [Word Formation (Appel Ranch Member), USNM 727j.]

PLATE 627.—Spiriferella.

PLATE 628

Spiriferella

Spiriferella embrithes, new species: 1–5, Dorsal, ventral, side, posterior, and anterior views, ×1, juvenile paratype USNM 152951d; 6–10, dorsal, ventral, posterior, side, and anterior views, ×1, young adult paratype USNM 152951g; 11, interior view of pedicle valve, ×1, paratype USNM 152951h; 12, interior view of broken brachial valve, ×1, paratype USNM 152951j; 13–17, dorsal, ventral, anterior, posterior and side views, ×1, adult holotype USNM 152951i; 18–19, dorsal and anteroventral views, ×1, showing mesial coils of spiralium, young adult paratype USNM 152951k. [Word Formation (China Tank Member), USNM 706c.]

Spiriferella sulcifer (Shumard): 20–23, Dorsal, ventral, side, and posterior views of young adult shell, ×1, hypotype USNM 152959a; 33–34, interior views of pedicle valve, ×1, ×2, hypotype USNM 152959b; 35–36, interior views of brachial valve, ×1, ×2, hypotype USNM 152959c. [Bell Canyon Formation (Rader Member), USNM 725f.]

24–28, Dorsal, ventral, side, posterior, and anterior views of young adult shell, ×1, neotype USNM 152958a. [Bell Canyon Formation (Rader Member), USNM 725g.]

29–30, Exterior and interior views, of brachial valve, ×1, hypotype USNM 152957q; 31–32, exterior and interior views of pedicle valve, ×1, hypotype USNM 152957o. [Bell Canyon Formation (Hegler Member), USNM 731.]

Spiriferella clypeata, new species: 37, Exterior view of brachial valve, portion enlarged to show ornament, ×4, paratype USNM 154552a (see Plate 627: figures 17, 18). [Word Formation (Appel Ranch Member), USNM 727j.]

PLATE 628.—Spiriferella.

PLATE 629

Spiriferella

Spiriferella gloverae, new species: 1, 2, Ventral and dorsal views, ×1, juvenile paratype USNM 152952r; 3, 4, exterior and interior views of juvenile pedicle valve, ×1, paratype USNM 152952v; 5, 6, exterior and interior views of juvenile brachial valve, ×1, paratype USNM 152952q: 7, 8, exterior and interior views of juvenile brachial valve, ×1, paratype USNM 152952u; 9–13, dorsal, ventral, side, anterior, and posterior views, ×1, adult holotype USNM 152952x; 14–16, exterior views, ×4, ×1, and interior view, ×1, of brachial valve, paratype USNM 152952s; 17–19, exterior and interior views, ×1, and exterior view, ×4, of pedicle valve enlarged to show ornament, paratype USNM 152952w; 20, 21, exterior views of brachial valve, ×1, ×4, paratype USNM 152952t. [Cherry Canyon Formation (Getaway Member), USNM 728.]

PLATE 629.—Spiriferella.

PLATE 630

Spiriferella

Spiriferella gravis, new species: 1–5, Dorsal, ventral, side, posterior, and anterior views, ×1, juvenile paratype USNM 152953g; 6–10, dorsal, ventral, side, posterior, and anterior views, ×1, young adult paratype USNM 152953k; 11–16, dorsal, ventral, side, posterior, and anterior views ×1, and dorsal view, ×4, enlarged to show ornament, adult paratype USNM 152953m; 17–21, dorsal, ventral, side, anterior, and posterior views, ×1, adult holotype USNM 152953r; 22–26, dorsal, ventral, side, anterior, and posterior views, ×1, elongate adult paratype USNM 152953s; 27, interior view of pedicle valve with attached spat, ×1, paratype USNM 152953c′; 28, interior view of brachial valve, ×1, paratype USNM 152953a′; 29, interior view of pedicle valve, ×1, paratype USNM 152953d′; 30, 31, exterior and interior views of pedicle valve, ×1, paratype USNM 152953b′; 32, side oblique view of broken shell with spire, ×1, paratype USNM 152953f′; 33, interior oblique view of pedicle valve, ×1, paratype USNM 152953e′; 34, side oblique view of broken shell with spire, ×1, paratype USNM 152953g′; 35–37, partial exterior view, ×4, and exterior and interior views, ×1, of brachial valve, paratype USNM 152953z; 38–40, exterior and interior views, ×1, and exterior view, ×4, to show ornamentation, paratype USNM 152953y. [Word Formation (lens between Willis Ranch and Appel Ranch members), USNM 706b.]

PLATE 630.—Spiriferella.

PLATE 631

Spiriferella and Martinia

[All ×1]

Spiriferella propria, new species: 1–5, Dorsal, ventral, side, anterior, and posterior views, juvenile paratype USNM 152955d; 6–10, dorsal, ventral, posterior, anterior, and side views, juvenile paratype USNM 152955e. [Word Formation (Appel Ranch Member), USNM 706d.]

11–15, Dorsal, ventral, anterior, posterior, and side views of large adult, holotype USNM 152956a. [Word Formation (Appel Ranch Member), USNM 719z.]

Spiriferella levis, new species: 16, 17, Exterior and interior views of pedicle valve, paratype USNM 152954h; 18, 19, exterior and interior views of brachial valve, paratype USNM 152954n; 20, 21, exterior and interior views of pedicle valve, holotype USNM 152954k. [Word Formation (lens between Willis Ranch and Appel Ranch members), USNM 706b.]

Spiriferella sulcifer (Shumard): 22–24, Dorsal, ventral and side views of shell illustrated by King (1931, pl. 40: figs. 2a-b), YPM 12414; 25–26, dorsal and ventral views of shell illustrated by King (1931, pl. 39: figs. 6a-c), YPM 12414 (sic). [Word Formation (Appel Ranch Member), R. E. King 247.]

Martinia fucina, new species: 27–31, Dorsal, ventral, side, posterior, and anterior views, juvenile paratype USNM 154553a; 32–36, Dorsal, ventral, side, anterior, and posterior views, adult holotype USNM 154553b. [Bone Spring Formation, AMNH 634.]

37, 38, Exterior and interior views of pedicle valve, paratype USNM 152394g; 39, 40, exterior and interior views of pedicle valve, paratype USNM 152394f; 41, exterior view of brachial valve with radial stripes, paratype USNM 152394m; 42, interior view of brachial valve, paratype USNM 152394k. [Bone Spring Formation, USNM 728f.]

Martinia causaria, new species: 43, Exterior view of pedicle valve, paratype USNM 152395a. [Cherry Canyon Formation (Getaway Member), USNM 728.]

44, Exterior view of brachial valve, holotype USNM 152397-1; 45, exterior view of large pedicle valve with slot shaped barnacle borings, paratype USNM 152397m. [Cherry Canyon Formation (Getaway Member), USNM 732.]

PLATE 631.—Spiriferella and Martinia.

PLATE 632

Eliva

Eliva shumardi, new species: [all hypotypes]: 1–5, Dorsal, ventral, side, posterior, and anterior views of small shell, ×1, USNM 118588a (illustrated by Girty, 1909, pl. 13: figs. 6–6a); 6–10, dorsal, ventral, side, posterior, and anterior views of small shell, ×1, USNM 118588b (illustrated by Girty, 1909, pl. 13: figs. 4–4a); 11–15, dorsal, ventral, side, posterior, and anterior views of average size shell, ×1, USNM 118588c (illustrated by Girty, 1909, pl. 13: figs. 2–2d). [Capitan Formation, USGS 2926 (green).]

16–20, Dorsal, ventral, side, posterior, and anterior views, ×1, young adult paratype USNM 154567a; 25–29, dorsal, ventral, side, posterior, and anterior views, ×1, adult holotype USNM 154567b. [Capitan Limestone, USNM 725k.]

21–22, Ventral and posterior views, ×1, young adult paratype USNM 154568a; 23, 24, exterior and interior views of pedicle valve, ×1, paratype USNM 154568b; 30, 31, exterior and interior views of brachial valve, ×1, paratype USNM 154568c; 32, 33, exterior and interior views of pedicle valve, ×1, paratype USNM 154568d; 34, 35, exterior and interior views of pedicle valve, ×1, paratype USNM 154568e; 42, 43, interior views, ×1, ×2, fragment of brachial valve, paratype USNM 154568f; 44–46, exterior view, ×1, interior views, ×2, ×1, brachial valve, paratype USNM 154568g; 47–49, exterior and interior views, ×1, interior view, ×2, brachial valve, paratype USNM 154568h. [Bell Canyon Formation, (Lamar Member), USNM 728p.]

36–38, Exterior view, ×1, interior views, ×1, ×2, pedicle valve, paratype USNM 154569a; 39–41, exterior view, ×1, interior views, ×2, ×1, brachial valve, paratype USNM 154569b; 50–52, exterior view, ×1, interior views, ×2, ×1, distorted brachial valve, paratype USNM 154569c; 53–54, interior views, ×1, ×2, pedicle valve, paratype USNM 154569d. [Bell Canyon Formation, (Lamar Member), USNM 725e.]

PLATE 632.—Eliva.

PLATE 633

Elivina, Rallacosta, and Eliva

Elivina compacta (Girty): 1–5, Ventral, dorsal, side, posterior, and anterior views of young adult shell, ×1, hypotype USNM 152966b; 6–10, ventral, dorsal, side, posterior, and anterior views of adult shell, ×1, hypotype USNM 152966c; 16–20, ventral, dorsal, side, anterior, and posterior views of adult shell, hypotype USNM 152966d. [Bell Canyon Formation (Lamar Member), USNM 737a.]

11–15, Ventral, dorsal, side, anterior, and posterior views, ×1, holotype USNM 118589 (illustrated by Girty, 1909, pl. 13: figs. 7–7d). [Capitan Formation, USGS 2926 (green).]

Elivina annectens, new species: 21–25, Ventral, dorsal, side, posterior, and anterior views, ×1, young adult holotype USNM 152963b. [Bell Canyon Formation (Pinery Member), USNM 731.]

26–28, Exterior and interior views, ×1, and interior view, ×2, of pedicle valve, paratype USNM 154563a. [Bell Canyon Formation (Rader Member), USNM 725g.]

29–31, Exterior and interior views, ×1, and interior view, ×2, of brachial valve, paratype USNM 154564a; 32–34, interior views, ×2, ×1, and exterior view, ×1, of pedicle valve, paratype USNM 154564b; 35–37, exterior and interior views, ×1, and interior view, ×2, of brachial valve, paratype USNM 152964a. [Bell Canyon Formation (Hegler or Pinery Member), USNM 733.]

Rallacosta species 2: 38, Interior view of pedicle valve, ×1, USNM 154958. [Bone Spring Formation, AMNH 625.]

Eliva inflata, new species: 39–43, Ventral, dorsal, side, posterior, and anterior views, ×1, young adult paratype USNM 152887c; 44–48, ventral, dorsal, anterior, posterior, and side views, ×1, adult paratype USNM 152887f; 49–53, ventral, dorsal, side, posterior, and anterior views, ×1, adult holotype USNM 152887]. [Capitan Limestone, USNM 750a.]

PLATE 633.—Elivina, Rallacosta, and Eliva.

PLATE 634

Elivina

Elivina detecta, new species: 1–5, Ventral, dorsal, side, posterior, and anterior views, ×1, juvenile paratype USNM 152968c; 6–10, ventral, dorsal, side, anterior, and posterior views, ×1, juvenile paratype USNM 152968e; 11–15, ventral, dorsal, side, posterior, and anterior views, ×1, young adult holotype USNM 152968f; 20–22, exterior and interior views, ×1, and interior view, ×2, of brachial valve, paratype USNM 152968h; 29–31, interior views ×2, ×1, and exterior view, ×1, of pedicle valve, paratype USNM 152968j.[Bell Canyon Formation (Lamar Member), USNM 738b.]

16, 17, Exterior and interior views of pedicle valve, ×1, paratype USNM 152969t; 18, 19, exterior and interior views of pedicle valve, ×1, paratype USNM 152969u; 26–28, exterior and interior views, ×1, and interior view, ×2, of brachial valve, paratype USNM 152969n; 32–34, exterior and interior views, ×1, and interior view, ×2, of pedicle valve, paratype USNM 152969k; 35–37, interior and exterior views, ×1, and interior view, ×2, of pedicle valve, paratype USNM 152969s. [Bell Canyon Formation (Lamar Member), USNM 738.]

23–25, Exterior and interior, ×1, and interior, ×2, of a ventral valve, paratype USNM 154566. [Bell Canyon Formation (Lamar Member), AMNH 40.]

38–40, Interior, ×2, and exterior and interior, ×1, of pedicle valve, paratype USNM 154565a; 41–43, exterior and interior, ×1, and interior, ×2, of brachial valve, showing cardinalia, paratype USNM 154565b; 44–46, interior and exterior, ×1, and interior, ×2, of large pedicle valve, paratype USNM 154565c; 47–49, exterior and interior, ×1, and interior, ×2, of large brachial valve, paratype USNM 154565d. [Bell Canyon Formation (Lamar Member), AMNH 347.]

PLATE 634.—Elivina.

PLATE 635

Neophricadothyris

Neophricadothyris bullata, new species: 1–1, Dorsal, ventral, side, and posterior views, ×1, juvenile paratype USNM 152486v; 5–8, dorsal, ventral, side, and posterior view, ×1, juvenile paratype USNM 152486d′; 9–13, dorsal, ventral, side, posterior, and anterior views, ×1, young adult paratype USNM 152486-1′; 14–16, dorsal, posterior, and ventral views, ×1, young adult paratype USNM 159486v′; 17–20, ventral, side, interior, and posterior views of young pedicle valve, ×1, paratype USNM 152485i; 21–24, interior, ventral, side, and posterior views of adult pedicle valve, ×1, paratype USNM 152485k; 25–26, ventral and dorsal oblique view, ×1, of young adult shell and ventral interior view, ×1, of shell broken to show primary lamella, paratype USNM 152485e; 27–30, ventral, interior, side, and posterior views of adult pedicle valve, ×1, paratype USNM 152485j; 31–32, interior and posterior views of articulated beak region, ×1, paratype shell USNM 152485d; 33–34, side and interior views of shell broken near socket, ×1, showing one crural base, paratype USNM 152485c; 35–36, exterior and interior views of brachial valve with remnant of pedicle valve beak, ×1, paratype USNM 152485a; 37–38, exterior and interior views of brachial valve, ×1, paratype USNM 152485f; 39–43, interior views of very young brachial valves, ×12, showing beginnings of formation of spires, paratypes, USNM 152485n–r; 44–45, exterior and interior views of brachial valve, ×1, paratype USNM 152485g; 46–47, exterior and interior views of brachial valve, ×1, paratype USNM 152485b; 48–49, exterior and interior views of brachial valve, ×1, paratype USNM 152485h; 57–60, dorsal, ventral, posterior, and anterior views, ×1, adult holotype USNM 152486g^2; 61, interior view of pedicle valve, ×3, showing delthyrial flanges, paratype USNM 152485-1; 63, exterior view of brachial valve with some spines preserved, ×3, paratype USNM 152485s; 64, interior view of pedicle valve with delthyrial flanges, ×3, paratype USNM 152485m. [Road Canyon Formation, USNM 702c.]

50, Interior view of broken shell with part of spire held in place by undissolved limestone, ×1, paratype USNM 152490a; 51, interior oblique view of broken shell with part of spire held by undissolved limestone, ×1, paratype USNM 152490b. [Cathedral Mountain Formation, USNM 702un.]

52–56, Dorsal, ventral, side, anterior, and posterior views, ×1, adult paratype USNM 154956. [Bone Spring Formation, AMNH 591.]

62, Dorsal view of juvenile shell with spines preserved, ×3, paratype USNM 152483. [Cathedral Mountain Formation, USNM 702a.]

PLATE 635.—Neophricadothyris.

PLATE 636

Neophricadothyris

Neophricadothyris catatona, new species: 1–4, Ventral, side, posterior, and anterior views of pedicle valve, ×1, paratype USNM 154558a; 18–21, dorsal, anterior, side, and posterior views of brachial valve, ×1, paratype USNM 154558b. [Bone Spring Formation, USNM 725c.]

5–8, Ventral, posterior, anterior and side views of pedicle valve, ×1, paratype USNM 152531a; 10–13, ventral, posterior, anterior, and side views of pedicle valve, ×1, paratype USNM 152532k; 9, 14–16, dorsal tilted, dorsal, anterior, and side views of brachial valve, ×1, paratype USNM 152531b; 26–28, ventral, side, and posterior views of large pedicle valve, ×1, paratype USNM 152532m. [Skinner Ranch Formation (Decie Ranch Member), USNM 720e.]

17, Exterior view of brachial valve, ×1, paratype USNM 154559a. [Skinner Ranch Formation, USNM 726h.]

22–25, Dorsal, side, posterior, and anterior views, ×1, holotype USNM 152994a. [Skinner Ranch Formation (lower), USNM 711q.]

Neophricadothyris? species undetermined: 29–33, Ventral, anterior, posterior, and side views, ×1, and posterior oblique view, ×2, of pedicle valve, USNM 154560a; 34–37, dorsal, side, anterior, adn posterior views of brachial valve, ×1, USNM 154560b; 38–41, ventral, anterior, posterior, and side views of pedicle valve, ×1, USNM 154560c; 42–45, dorsal, side, anterior, and posterior views of brachial valve, ×1, USNM 154560d. [Cathedral Mountain Formation, USNM 721u.]

PLATE 636.—Neophricadothyris.

PLATE 637

Neophricadothyris

Neophricadothyris cordata, new species: 1–4, Dorsal, ventral, side, and anterior views, ×1, juvenile paratype USNM 152505a; 5–8, dorsal, ventral, side, and anterior views, ×1, juvenile paratype USNM 152505b; 19–22, dorsal, ventral, side, and anterior views, ×1, adult paratype USNM 152505i; 23–26, dorsal, ventral, side, and anterior views, ×1, adult holotype USNM 152505j; 27–30, dorsal, ventral, side, and anterior views, ×1, adult paratype USNM 152505k; 31–34, ventral, posterior, anterior, and interior views of pedicle valve, ×1, paratype USNM 152505m; 35–38, dorsal, posterior, anterior, and interior views of brachial valve, ×1, paratype USNM 152505n; 40, interior view of pedicle valve with deeply impressed heart-shaped muscle marks, ×1, paratype USNM 152505o; 41, interior view of pedicle valve, ×1, paratype USNM 152505p; 42, tilted interior view of pedicle valve, ×1, paratype USNM 152505q; 45–46, interior views of brachial valve with distinct muscle marks, ×2, ×1, paratype USNM 152505r. [Road Canyon Formation, USNM 703d.]

9–13, Ventral, dorsal, side, anterior, and posterior views, ×1, spiny paratype USNM 152506a; 14–18, dorsal, ventral, side, posterior, and anterior views, ×1, paratype USNM 152506b; 39, side view of shell broken to show remnant of spire, ×1, paratype USNM 152506c; 43–44, interior views of brachial valve with muscle marks and brachiophore bases, ×1, ×3, paratype USNM 152506d; 47–48, interior views of pedicle valve with muscle marks, ×1, ×3, USNM 152506e. [Road Canyon Formation, USNM 707e.]

PLATE 637.—Neophricadothyris.

PLATE 638

Neophricadothyris

[All ×1]

Neophricadothyris crassibecca, new species: 1–4, Ventral, dorsal, side, and posterior views, juvenile paratype USNM 152995g; 5–9, ventral, dorsal, side, posterior, and anterior views, juvenile paratype USNM 152995n; 10–13, dorsal, side, posterior, and anterior views, young adult paratype USNM 152995t; 19–23, ventral, dorsal, side, posterior, and anterior views, adult holotype USNM 152995z. [Road Canyon Formation (base) USNM 721o.]

14–18, Ventral, dorsal, side, anterior, and posterior views, adult paratype USNM 152541a; 29, interior view of articulated posterior ends of both valves, pedicle valve up, paratype USNM 152541b; 30, interior view of brachial valve, paratype USNM 152541c; 31, interior view of brachial valve tilted backwards, paratype USNM 152541d; 32, interior view of brachial valve, paratype USNM 152541e; 33, interior view of pedicle valve, paratype USNM 152541f. [Road Canyon Formation, USNM 719x.]

24–28, Ventral, dorsal, side, posterior, and anterior views, adult paratype USNM 154561. [Road Canyon Formation, USNM 721s.]

Neophricadothyris conara, new species: 34, 35, Ventral and side oblique views, juvenile paratype USNM 152534d; 36, 37, exterior and interior views of brachial valve, paratype USNM 152534g; 38, 39, exterior and interior views of pedicle valve, paratype USNM 152534o; 40, 41, exterior and interior views of another pedicle valve, paratype USNM 152534q; 42, 43, exterior and interior views of pedicle valve, paratype USNM 152534r; 44, 45, exterior and interior views of brachial valve, paratype USNM 152534z; 46–50, ventral, dorsal, side, posterior, and anterior views, adult holotype USNM 152534p. [Word Formation (lens between Willis and Appel Ranch members), USNM 706b.]

51–54, Ventral, dorsal, anterior, and posterior views, large paratype USNM 154562a. [Word Formation (Appel Ranch Member), USNM 731 z.]

Neophricadothyris species 1: 55–59, Ventral, dorsal, posterior, anterior, and side views of an unusually large specimen, USNM 153473. [Cathedral Mountain Formation (base), USNM 702.]

PLATE 638.—Neophricadothyris.

PLATE 639

Neophricadothyris

[All ×1]

Neophricadothyris transversa, new species: 1–5, Ventral, dorsal, side, anterior, and posterior views, juvenile paratype USNM 152513c; 6–10, ventral, dorsal, side, posterior, and anterior views, young adult paratype USNM 152513h; 11–15, ventral, dorsal, side, posterior, and anterior views, atypically narrow paratype USNM 152513i; 22–26, ventral, dorsal, side, posterior, and anterior views, encrusted adult holotype USNM 152513k. [Neal Ranch Formation, USNM 701c.] 152509b. [Neal Ranch Formation, USNM 701a.]

16, Interior view of posterior part of articulated shell, brachial valve up, paratype USNM 152509a; 17–21, ventral, dorsal, side, posterior, and anterior views, adult paratype USNM 152509b. [Neal Ranch Formation, USNM 701a.]

27, Exterior of a large pedicle valve, paratype USNM 152514b; 28, interior of incomplete specimen, paratype USNM 152514a. [Neal Ranch Formation, USNM 701d.]

Neophricadothyris, species 2: 29–33, Ventral, dorsal, side, posterior, and anterior views of large shell, figured specimen USNM 153474; 34, side oblique view of silicified detached half of spire from preceding specimen. [Cathedral Mountain Formation, USNM 702.]

PLATE 639.—Neophricadothyris.

PLATE 640

Anomaloria

[All hypotypes unless otherwise noted]

Anomaloria anomala, Cooper and Grant: 1–4, Dorsal, side, anterior, and posterior views of juvenile, ×1, USNM 152999b; 5–8, dorsal, side, anterior, and posterior views of juvenile, ×1, USNM 152999e; 21, 45, interior view, ×1, and interior view of hinge region of brachial valve, ×3, USNM 152999g; 33–34, interior views of pedicle valve with delthyrial cover and distinct muscle marks, ×1, ×3, USNM 152999h; 42, 43, interior views of pedicle valve, ×1, ×3, USNM 152999i; 48, 49, interior views of brachial valve with sockets and muscle marks, ×1, ×3, USNM 152999j. [Bell Canyon Formation (Lamar Member), USNM 725e.]

9–14, Dorsal, ventral, side, anterior, and posterior views, ×1, posterodorsal view, ×3, showing delthyrial cover, USNM 152998i; 15, interior view of brachial valve, ×1, USNM 152998k; 16, interior view of pedicle valve, ×1, USNM 152998m; 17, interior view of brachial valve, ×1, USNM 152998n; 31, posterodorsal view of shell tilted to show delthyrial cover, ×3, USNM 152998j; 32, interior view of pedicle valve, ×1, USNM 152998p; 46–17, interior views of brachial valve, ×1, ×3, USNM 152998o. [Bell Canyon Formation (Lamar Member), USNM 738b.]

18, Interior view of pedicle valve, ×1, USNM 153197e; 19, interior view of brachial valve, ×1, USNM 153197f; 20, interior view of brachial valve, ×1, USNM 153197g; 35–37, dorsal and side views, ×1, posterior view, ×2, USNM 153197b; 38–41, dorsal, side, and anterior views, ×1, posterior view, ×1.5, adult paratype USNM 153197c; 44, interior view of articulated cardinal area, ×3, showing hinge teeth in sockets, paratype USNM 153l97d. [Bell Canyon Formation (Lamar Member), USNM 728p.]

22–25, Dorsal, side, anterior, and posterior views of adult, ×1, USNM 153001d. [Bell Canyon Formation (Lamar Member), USNM 737a.]

26–30, Dorsal, ventral, side, anterior, and posterior (pedicle valve up) views of adult, ×1, USNM 153000f. [Capitan Formation, USNM 750.]

PLATE 640.—Anomaloria.

PLATE 641

Astegosia

[All hypotypes, all ×1]

Astegosia subquadrata (Girty): 1–4, Ventral, side, posterior, and anterior views of juvenile shell, USNM 154570a; 5–8, ventral, side, posterior, and anterior views of juvenile shell, USNM 154570b; 14–17, ventral, side, anterior, and posterior views of juvenile shell, USNM 154570c. [Bell Canyon Formation (Lamar Member), USNM 728p.]

9–13, Dorsal, ventral, side, posterior, and anterior views of juvenile shell, USNM 152996h; 18–22, dorsal, ventral, side, posterior, and anterior views of juvenile shell, USNM 152996-1; 23–27, dorsal, ventral, side, posterior, and anterior views of young adult shell, USNM 152996r; 28–32, dorsal, ventral, side, posterior, and anterior views of young adult shell, USNM 152996u; 33–37, dorsal, ventral, side, posterior, and anterior views of adult shell, USNM 152996y; 38–42, dorsal, ventral, side, anterior, and posterior views of adult shell, USNM 152996z. [Bell Canyon Formation (Lamar Member), USNM 738b.]

43–47, Dorsal, ventral, side, posterior, and anterior views of adult shell, USNM 152481b; 53–57, dorsal, ventral, side, posterior, and anterior views of large adult shell, USNM 152481i. [Capitan Formation, USNM 750.]

48–52, Dorsal, ventral, side, posterior, and anterior views of adult shell, USNM 152480q′. [Bell Canyon Formation (Lamar Member), USNM 737a.]

PLATE 641.—Astegosia.

PLATE 642

Astegosia

[All hypotypes]

Astegosia subquadrata (Girty): 1, Interior view of pedicle valve, ×1, USNM 152476a; 2, interior view of brachial valve, ×1, USNM 152476b; 16, interior view of pedicle valve, ×2, USNM 152476c. [Bell Canyon Formation (Lamar Member), USNM 738b.]

3, Interior view of pedicle valve, ×1, USNM 152474a; 10, interior view of pedicle valve, with many internally healed barnacle borings, ×1, USNM 152474b. [Bell Canyon Formation (Lamar Member), USNM 738.]

4, Exterior view of pedicle valve, ×1, USNM 154572a; 6, interior view of pedicle valve, ×1.5, USNM 154572b; 18, interior view of pedicle valve, ×1.5, USNM 154572c; 19, interior view of brachial valve, ×1, USNM 154572d. [Bell Canyon Formation (Lamar Member), USNM 725e.]

5, Interior view of pedicle valve, ×1, USNM 154571a; 7, interior view of brachial valve, ×1, USNM 154571e; 9, interior view of brachial valve, ×1.5, USNM 154571b; 11, interior view of brachial valve, ×1, USNM 154571f; 13, interior view of pedicle valve, ×1, USNM 154571c; 17, interior view of pedicle valve, ×1.5, USNM 154571d. [Bell Canyon Formation (Lamar Member), AMNH 347.]

8, Interior view of brachial valve, ×1, USNM 154570d; 12, interior view of brachial valve, ×1, USNM 154570e; 14, interior view of brachial valve, ×2, USNM 154570f; 15, exterior view of brachial valve with concentric frills, ×2, USNM 154570g; 20, exterior view of brachial valve with ornament, ×2, USNM 154570h. [Bell Canyon Formation (Lamar Member), USNM 728p.]

PLATE 642.—Astegosia.

PLATE 643

Martinia

[All ×1]

Martinia miranda, new species: 1–4, Dorsal, ventral, side, and posterior views, juvenile paratype USNM 152382a; 35–39, dorsal, ventral, side, anterior, and posterior views, adult holotype USNM 152381a. [Cathedral Mountain Formation (lower), USNM 702a.]

5–8, Dorsal, side, anterior, and posterior views, juvenile paratype USNM 152387c. [Cathedral Mountain Formation (base), USNM 702 low.]

9–12, Dorsal, ventral, side, and posterior views, juvenile paratype USNM 152391. [Cathedral Mountain Formation (base), USNM 703b.]

13–17, Dorsal, anterior, side, ventral, and posterior views, young adult paratype USNM 152380. [Cathedral Mountain Formation (base), USNM 702.]

18–21, Dorsal, ventral, side, and posterior views, adult paratype USNM 152384r; 22, 23, exterior and interior views of elongate pedicle valve, paratype USNM 152383c; 24, 25, exterior and interior views of brachial valve, paratype USNM 152383e; 26, interior view of adult pedicle valve with pallial lines, paratype USNM 152383d; 27, 28, exterior and interior views of adult pedicle valve, paratype USNM 152383f; 29, 30, exterior and interior views pedicle valve, paratype USNM 152383a; 31, 32, exterior and interior views of brachial valve, paratype USNM 152383b; 33, 34, exterior and interior views of brachial valve, paratype USNM 152383g. [Cathedral Mountain Formation (base), USNM 702b.]

PLATE 643.—Martinia.

PLATE 644

Martinia

Martinia rhomboidalis Girty [all hypotypes]: 1–5, Dorsal, ventral, side, posterior, and anterior views of young adult shell, ×1, USNM 108551a; 6–10, dorsal, ventral, side, posterior, and anterior views of young adult shell, ×1, USNM 108551b. [Capitan Formation, USNM 750e.]

11–15, Dorsal, ventral, side, posterior, and anterior views, of young adult shell, ×1, USNM 152350f. [Bell Canyon Formation (Lamar Member), USNM 738.]

16–17, Exterior and interior views of pedicle valve, ×1, USNM 154554a; 18–19, exterior and interior views of brachial valve, ×1, USNM 154554b. [Bell Canyon Formation (Lamar Member), USNM 725e.]

20–21, Exterior and interior views of brachial valve, ×1, USNM 154555a. [Bell Canyon Formation (Lamar Member), USNM 728p.]

22–23, Exterior and interior views of pedicle valve, ×1, USNM 154556a. [Bell Canyon Formation (Lamar Member], AMNH 347.]

Martinia exigua, new species: 24–30, Dorsal views, ×1, ×2, ×4, side view, ×2, anterior and ventral views, ×1, ×2, and ventral view, ×2, of adult shell, holotype USNM 153344e; 31–36, dorsal, posterior, and side views, ×1, ×2, adult paratype USNM 153344a; 37–40, exterior views, ×1, ×2, interior view of hinge area, ×4, and interior view, ×2, of brachial valve, paratype USNM 153344h; 41–44, exterior views, ×1, ×2, interior view, ×2, and interior view of hinge area, ×4, of pedicle valve, paratype USNM 153344f. [Neal Ranch Formation, USNM 727e.]

Martinia renfroae, new species: 45–49, Dorsal, ventral, side, anterior, and posterior views, ×1, adult holotype USNM 152378. [Graham Formation (Jacksboro Member), USNM 510g.]

Martinia species 1: 50–51, Side and exterior views of brachial valve, ×1, figured specimen 152521a; 52–53, side and exterior views of pedicle valve, ×1, figured specimen USNM 152521b. [Skinner Ranch Formation (base), USNM 711d.]

Martinia cruenta, new species: 54–57, Dorsal, posterior, anterior, and side views of exfoliated shell, ×1, figured specimen USNM 152376a. [Float from Hess or Neal Ranch Formation, USNM 719q.]

PLATE 644.—Martinia.

PLATE 645

Martinia

[All hypotypes]

Martinia rhomboidalis Girty: 1–2, Exterior and interior views, ×1, juvenile pedicle valve, USNM 154554c; 3–4, exterior and interior views of pedicle valve, ×1, USNM 154554d; 36–37, exterior and interior views of brachial valve with muscle marks, ×1, USNM 154554e. [Bell Canyon Formation (Lamar Member), USNM 725e.]

5–6, Exterior and interior views of pedicle valve, ×1, USNM 154556b; 13–14, exterior and interior views of pedicle valve, ×1, USNM 154556c; 15–16, exterior and interior view of pedicle valve, ×1, USNM 154556d; 17–18, exterior and interior views of thickened brachial valve, ×1, USNM 154556e; 19–20, exterior and interior views of brachial valve, ×1, USNM 154556f; 23–24, exterior and interior views of pedicle valve, ×1, USNM 154556g; 29–30, exterior and interior views of brachial valve, ×1, USNM 154556h; 31–32, exterior and interior views of brachial valve with borings internally healed, ×1, USNM 154556i; 33–34, exterior and interior views of brachial valve, ×1, USNM 154556j. [Bell Canyon Formation (Lamar Member), AMNH 347.]

7–8, Exterior and interior views of brachial valve, ×1, USNM 152349q′; 9–10, exterior and interior views of pedicle valve with elongate tongue of sulcus, ×1, USNM 152349v′; 25–26, exterior and interior views of pedicle valve, ×1, USNM 152349s′; 27–28, exterior and interior views of brachial valve with borings that penetrate, some partly healed, ×1, USNM 152349t. [Bell Canyon Formation (Lamar Member), USNM 738.]

11–12, Exterior and interior views of brachial valve with healed borings, ×1, USNM 154555b; 21–22, exterior and interior views of pedicle valve with complex pallial system, ×1, USNM 154555c; 35, interior views of pedicle valve, ×1, USNM 154555d. [Bell Canyon Formation (Lamar Member), USNM 728p.]

38–39, Interior views of brachial valve with primary lamella, ×1, ×2, USNM 154557a. [Bell Canyon Formation (Lamar Member), AMNH 40.]

PLATE 645.—Martinia.

PLATE 646

Rallacosta and Heteraria

Rallacosta species 1: 1–3, Dorsal, interior, and side views of brachial valve ×1, USNM 153191b; 4–6, ventral, interior, and side views of pedicle valve, ×1, USNM 153191a. [Cherry Canyon Formation (Getaway Member), USNM 728.]

Rallacosta species 2: 7–9, Ventral, interior, and side views of pedicle valve, ×1, USNM 153192. [Bone Spring Formation, AMNH 629.]

Heteraria blakemorei, new species: 10–13, Dorsal, interior, anterior, and side views of brachial valve, ×1, paratype USNM 153190e; 14–17, ventral, posterior, interior and side views of pedicle valve, ×1, paratype USNM 153190c; 18–22, dorsal, side, interior, and posterior views, ×1, and interior view, ×2, of brachial valve, paratype USNM 153190d; 23, exterior view of pedicle valve, ×1, paratype USNM 153190f; 24–28, ventral, interior, anterior, and side views, ×1, and interior view, ×2, of pedicle valve, holotype USNM 153190a; 29–34, interior view, ×1, ×2, interior view tilted, ×2, and dorsal, side, and anterior views, ×1, of brachial valve, paratype USNM 153190b. [Cathedral Mountain Formation, USNM 721u.]

PLATE 646.—Rallacosta and Heteraria.

PLATE 647

Rallacosta

Rallacosta actina, new species: 1–5, Dorsal views, ×1, ×2, and side, posterior, and anterior views, ×1, immature adult holotype USNM 152971d; 6–10, side, ventral, anterior, interior, and posterior views of abraded and bored pedicle valve, ×1, paratype USNM 152971e; 11–15, dorsal, side, anterior, and posterior views, ×1, and interior view, ×2, of broken brachial valve, paratype USNM 152971c. [Cathedral Mountain Formation, USNM 702.]

16–20, Interior, posterior, anterior, side, and ventral views of pedicle valve, ×1, paratype USNM 152970m; 21–25, dorsal, side anterior, and posterior views, ×1, and dorsal view, ×2, of brachial valve, paratype USNM 152970k; 26–30, 37, side, posterior anterior, ventral, and interior views, ×1, and ventral view, ×2 (fig. 37) of pedicle valve, paratype USNM 152970-1; 34, exterior view of pedicle valve, ×2, paratype USNM 152970n; 35, exterior view of brachial valve with circular boring, ×2, paratype USNM 152970o; 36, exterior view of pedicle valve, ×2, paratype USNM 152970p. [Cathedral Mountain Formation, USNM 702b.]

31–33, Exterior and interior views, ×2, and interior view, ×1, of brachial valve, paratype USNM 152972. [Cathedral Mountain Formation, USNM 702inst.]

Rallacosta xystica, new species: 38–43, Exterior views, ×1, ×2, and interior, side, posterior, and anterior views, ×1, of brachial valve with circular boring, paratype USNM 152976d; 44–49, interior, dorsal, anterior, posterior, and side views, ×1, and dorsal view, ×2, of brachial valve, holotype USNM 152976e; 50–54, ventral, interior, posterior, anterior, and side views, ×1, of pedicle valve, paratype USNM 152976g. [Cathedral Mountain Formation, USNM 703b.]

PLATE 647.—Rallacosta.

PLATE 648

Rallacosta

Rallacosta imporcata, new species: 1–4, Dorsal, anterior, posterior, and side views, ×1, of brachial valve, paratype USNM 152973w; 5–8, dorsal, anterior, posterior, and side views of brachial valve, ×1, paratype USNM 152973x; 9–13, ventral, interior, anterior, side, and posterior views of pedicle valve, ×1, paratype USNM 152973t; 14–19, exterior views, ×1, ×2, and interior, side, anterior, and posterior views, ×1, of pedicle valve, holotype USNM 152973n; 20–25, exterior views, ×2, ×1, and posterior, anterior, side, and interior views, ×1, of brachial valve, paratype USNM 152973j; 26–30, ventral, posterior, anterior, and side views, ×1, and interior view (one side broken) ×2, paratype USNM 152973v; 31–36, dorsal, side, anterior, and posterior views, ×1, and exterior and interior views, ×2, of brachial valve, paratype USNM 152973y; 37–42, ventral, anterior, posterior, and side views, ×1, and exterior and interior views, ×2, pedicle valve, paratype USNM 152973u; 43–48, dorsal, interior, anterior, posterior, and side views, ×1, and dorsal view ×2, of brachial valve, paratype USNM 152973q. [Bell Formation (Rader Member), USNM 725f.]

Rallacosta laminata, new species: 49–52, Dorsal, side, anterior, and posterior views of brachial valve, ×1, paratype USNM 152974u; 53–56, ventral, anterior, posterior, and side views of pedicle valve, ×1, paratype USNM 152974y; 57–60, ventral, side, anterior, and posterior views of pedicle valve, ×1, paratype USNM 152975b; 61–65, ventral, interior, side, posterior, and anterior views of pedicle valve, ×1, paratype USNM 152975c; 66–70, dorsal, interior, posterior, anterior, and side views of brachial valve, ×1, paratype USNM 152975d; 71–75, dorsal, interior, side, anterior, and posterior views of brachial valve, ×1, holotype USNM 152975g; 76–77, interior views of brachial valve, ×2, ×1, paratype USNM 152975i. [Cathedral Mountain Formation (base), USNM 708u.]

PLATE 648.—Rallacosta.

PLATE 649

Martinia, Neophricadothyris, Astegosia, and Composita

[All ×1]

Martinia nealranchensis, new species: 1–4, Dorsal, ventral, anterior, and posterior views, juvenile paratype USNM 154957a; 5–9, dorsal, ventral, side, anterior, and posterior views, young adult paratype USNM 154957b; 10–14, dorsal, ventral, side, posterior, and anterior views, adult holotype USNM 154957c. [Neal Ranch Formation (bed 4), USNM 727e.]

Martinia wolfcampensis R. E. King: 15–19, Dorsal, ventral, posterior, side, and anterior views, holotype YPM 12295 (figured by R. E. King, 1931, pl. 40: fig. 9a–d). [Gaptank Formation (Uddenites-bearing Shale Member), R. E. King 88s.]

Neophricadothyris bullata, new species: 20–24, Dorsal, ventral, anterior, side, and posterior views, paratype YPM 12370 (specimen figured by R. E. King, 1931, pl. 40: figs. 7a–c, under name Squamularia guadalupensis (Shumard). [Hess Formation, R. E. King 1.]

Astegosia subquadrata (Girty): 25–26, Dorsal and side views of adult shell, hypotype USNM 154960. [Bell Canyon Formation (Lamar Member), USNM 728p.]

Neophricadothyris cordata, new species: 27–30, Dorsal, side, posterior, and anterior views, adult paratype USNM 154959. [Cibolo Formation (Thin-bedded zone of Udden), USNM 738-1.]

Martinia rhomboidalis Girty: 31–33, Dorsal, anterior, and side views of distorted juvenile shell, paratype USNM 154961a; 34–35, interior and exterior views of adult brachial valve paratype USNM 154961b; 36–37, interior and exterior views of large distorted pedicle valve, paratype USNM 154961–c. [Bell Canyon Formation (Lamar Member), USNM 728p.]

Composita strongyle, new species: 38–40, Dorsal, side, and anterior views of adult specimen with cemented Derbyia, paratype USNM 154962a; 41–43, anterior, dorsal, and side views of adult shell with bryozoan overgrowths, paratype USNM 154962b. [Neal Ranch Formation (bed 4), USNM 727e.]

PLATE 649.—Martinia, Neophricadothyris, Astegosia, and Composita.

PLATE 650

Cleiothyridina

Cleiothyridina ciriacksi, new species: 1–5, Anterior, ventral, side, posterior, and dorsal views of a complete specimen, ×1, paratype USNM 154386g; 6–10, side, ventral, posterior, dorsal, and anterior views, ×1, holotype USNM 154386h; 11–13, side, dorsal, and anterior views, ×2, of the holotype; 14, anterior portion of the holotype, ×4, showing the spines; 15, 16, interior and exterior tilted to show the dental plates of a pedicle valve, ×1.5, paratype USNM 154386k; 17, 18, interior of two brachial valves, ×1.5, ×3, paratypes USNM 154386j, i. [Park City Formation (Franson Member), USNM 763.]

Cleiothyridina mulsa, new species: 19, Ventral, posterior, side, anterior, and dorsal views of a complete specimen, ×1, paratype USNM 152459h; 20–24, ventral, dorsal, anterior, posterior, and side views, ×2, of the preceding paratype; 25, ventral, posterior, side, anterior, and dorsal views, ×1, holotype USNM 152459i; 26–30, side, dorsal, anterior, posterior, and ventral views, ×2, holotype; 31, brachial valve of the holotype, ×3, tilted to show the ornament; 32, 33, interior and tilted views of the pedicle valve, ×3, showing dental plates, paratype USNM 152459-1; 34, 35, interior and tilted views of the brachial valve interior, ×3, showing the hinge plate, paratype USNM 152459k. [Skinner Ranch Formation (base), USNM 705a.]

Cleiothyridina nana, new species: 36–41, Dorsal view, ×1, and anterior, posterior, side, dorsal and ventral views, ×4, holotype USNM 154387a; 42–47, dorsal view, ×1, and ventral, dorsal, anterior, posterior, and side views, ×2, paratype USNM 154387b. [Road Canyon Formation, USNM 710u.]

48, Interior of the brachial valve, ×4, showing the hinge plate, paratype USNM 152456a; 49, exterior of the brachial valve, ×6, showing the ornament, paratype USNM 152456b. [Road Canyon Formation, USNM 709c.]

84–88, Dorsal, posterior, side, anterior, and ventral views, ×4, paratype USNM 154390a; 89–93, posterior, dorsal, anterior, side, and ventral views of another complete specimen, ×4, paratype USNM 154390b; 94, interior of the brachial valve, ×4, showing the hinge plate, paratype USNM 154390c; 95–99, dorsal, posterior, side, anterior, and ventral views of a complete specimen, ×4, holotype USNM 154390d. [Road Canyon Formation, USNM 722f.]

Cleiothyridina piluaris, new species: 50, Anterior, posterior, side, ventral, and dorsal views of a complete specimen devoid of spines, ×1, paratype USNM 152461d; 51–55, anterior, posterior, side, dorsal, and ventral views of a specimen preserving some of its spines, ×2, paratype USNM 152461v; 56–63, side, anterior, and dorsal views, ×2, and posterior, ventral, side, dorsal, and anterior views, ×2, and posterior, ventral, side, dorsal, and anterior views, ×1, holotype USNM 152461q; 81, 82, interior of the pedicle valve tilted and interior view, ×1.5, paratype USNM 152461u; 83, interior of the brachial valve, ×2, showing hinge plate and pallial marks, paratype USNM 152461s. [Bell Canyon Formation (Lamar Member), USNM 738b.]

64–71, Ventral, posterior, anterior, side, and dorsal views, ×1, and anterior, side, and dorsal views, ×2, of a complete specimen devoid of spines, paratype USNM 154388a; 80, interior of a brachial valve, ×2, showing the hinge plate and pallial marks, paratype USNM 154388b. [Bell Canyon Formation (Lamar Member), USNM 725e.]

72–76, Anterior, side, posterior, dorsal, and ventral views of a specimen preserving some of its spines, ×2, paratype USNM 154389a; 77–79, anterior, side, and dorsal views of another specimen with spines, ×2, paratype USNM 154389b. [Bell Canyon Formation (Lamar Member), AMNH 40.]

PLATE 650.—Cleiothyridina.

PLATE 651

Cleiothyridina and Nucleospira

Cleiothyridina rectimarginata, new species: 1–6, Anterior, posterior, side, ventral, and dorsal views, ×1, and posterior, ventral, side, anterior, and dorsal views, ×2, paratype USNM 152467a. [Neal Ranch Formation (beds 12–14 of P. B. King), USNM 701d.]

7, 8, Side and dorsal views of a complete specimen, ×2, paratype USNM 154391a; 9–13, anterior, side, posterior, ventral, and dorsal views of a complete specimen preserving some of its spines, ×2, paratype USNM 152471-1; 14–18, anterior, posterior, side ventral, and dorsal views of a complete specimen with some spines, ×2, holotype USNM 152471o; 19, 20, interior and tilted views of a pedicle valve, ×2, paratype USNM 154391c; 21, 22, tilted and interior views of a brachial valve, ×4, showing the hinge plate, paratype USNM 154391d; 23, partial side view of a complete individual broken to show the spire, ×4, paratype USNM 154391b. [Neal Ranch Formation (beds 12–14 of P. B. King), USNM 701k.]

24, 25, Interior of two brachial valves, ×2, showing the hinge plate, paratypes USNM 154392a, b; 26–30, anterior, side, posterior, ventral, and dorsal views of a stout specimen, ×2, paratype USNM 152469n; 31–36, posterior, anterior, side, ventral, and dorsal views, ×2, and dorsal view, ×1, of another strongly convex specimen, paratype USNM 152469k; 37–42, dorsal view, ×1, and posterior, anterior, side, ventral, and dorsal views, ×2, of complete individual with spines, paratype USNM 152469j; 43, exterior of a brachial valve preserving some of its spines, ×3, paratype USNM 154392c; 44, dorsal view of a complete specimen preserving some of its spines, ×3, paratype USNM 154392d. [Neal Ranch Formation (beds 12–14 of P. B. King), USNM 701h.]

Nucleospira cunctata, new species: 45–50, Ventral, posterior, side, anterior, and dorsal views, ×1, and anterior, posterior, side, dorsal, and ventral views, ×4, holotype USNM 152453z;.51–56, ventral, posterior, side, anterior, and dorsal views, ×1, and anterior, posterior, side, dorsal and ventral views, ×4, of a complete specimen, paratype USNM 152453g′; 57, ventral, posterior, side, anterior, and dorsal views of a complete specimen, ×1, paratype USNM 152453h′; 58, interior of a brachial valve, ×6, showing the anterior side of the cardinal process, paratype USNM 154393a; 59, posterior of the preceding specimen, ×4, showing the posterior side of the cardinal process; 60, 61, interior of a pedicle valve, ×4, and the same interior tilted to show the median septum and dental plates, ×6, paratype USNM 154393b; 62, 63, side and oblique side views, ×6, showing the jugum of the spire, paratype USNM 154393c; 64–66, tilted, side, oblique, and side views of another complete specimen, ×6, showing the spire, paratype USNM 154393d; 67, tilted interior of a brachial valve, ×4, showing the cardinal process, paratype USNM 154393e; 68, 69, interior of two pedicle valves, ×4, showing the apical plate, paratype USNM 155118a, b; 70, posterior of a brachial valve, ×4, showing the cardinal process, paratype USNM 154393f; 71, interior of a brachial valve in anterior oblique view, ×6, showing the jugum of the spire, paratype USNM 154393g; 72, brachial valve tilted posteriorly to show the interior side of the cardinal process, ×6, paratype USNM 154393h. [Cathedral Mountain Formation (base), USNM 708u.]

Cleiothyridina species undetermined: 73–77, Anterior, posterior, ventral, side, and dorsal views of a complete specimen with spines, ×2, figured specimen USNM 154394. [Hueco Canyon Formation, USNM 499b═725z.]

PLATE 651.—Cleiothyridina and Nucleospira.

PLATE 652

Composita

[All ×1]

Composita affinis Girty [all hypotypes]: 1–4, Ventral, side, anterior, and posterior views of small juvenile shell, USNM 153002a; 5–8, ventral, side, posterior, and anterior views of juvenile shell, USNM 153002b; 9–12, ventral, side, posterior, and anterior views of juvenile shell, USNM 153002c; 13–16, ventral, side, anterior, and posterior views of juvenile shell, USNM 153002d; 17–21, ventral, dorsal, side, posterior, and anterior views of adult shell, USNM 153002e; 22–23, exterior and interior views of pedicle valve, USNM 153002f; 24–28, ventral, dorsal, side, posterior, and anterior views of adult shell, USNM 153002g; 29–30, exterior and interior views of brachial valve, USNM 153002h; 31–32, exterior and interior views of pedicle valve with distinct muscle, pallial, and genital markings, USNM 1530U2i; 33–37, ventral, dorsal, side, posterior, and anterior views of adult shell, USNM 153002j; 38–39, exterior and interior views of brachial valve, USNM 153002k; 40–44, ventral, dorsal side, posterior, and anterior views of adult shell, USNM 153002m. [Bell Canyon Formation (Lamar Member), USNM 738.]

Composita apheles, new species: 45–49, Ventral, dorsal, side, posterior, and anterior views, juvenile paratype USNM 154537a; 50–54, ventral, dorsal, side, posterior, and anterior views, juvenile paratype USNM 154537b; 55–59, ventral, dorsal, side, anterior, and posterior views, juvenile paratype USNM 154537c; 60–64, ventral, dorsal, side, anterior, and posterior views, juvenile paratype USNM 154537d; 69–73, ventral, dorsal, side, posterior, and anterior views, young adult paratype USNM 154537e; 74–78, ventral, dorsal, side, posterior, and anterior views, adult holotype USNM 154537f; 88, ventral view of shell broken to show spire, paratype USNM 154537g. [Skinner Ranch Formation (Decie Ranch Member), USNM 720e.]

65–68, Ventral, side, posterior, and anterior views, young adult paratype USNM 153003a; 84–87, ventral, side, anterior, and posterior views, adult paratype USNM 153003b. [Skinner Ranch Formation (Decie Ranch Member), USNM 705a.]

79–83, Ventral, dorsal, side, posterior, and anterior views of large and somewhat crushed adult, paratype USNM 154536a. [Skinner Ranch Formation (Decie Ranch Member), USNM 727u.]

PLATE 652.—Composita.

PLATE 653

Composita

Composita costata, new species: 1–4, Ventral and dorsal views, ×1, ×2, adult holotype USNM 153006a; 5–7, interior views, ×1, ×2, and exterior view, ×2, of pedicle valve, paratype USNM 153006b; 8–10, interior views, ×1, ×2, and exterior view, ×2, of brachial valve, paratype USNM 153006c. [Bone Spring Formation, USNM 725y.]

Composita apsidata, new species: 11–15, Ventral, dorsal, side, posterior, and anterior views, ×1, juvenile paratype USNM 153004a; 16–20, ventral, dorsal, side, anterior, and posterior views, ×1, juvenile paratype USNM 153004b; 21–25, ventral, dorsal, side, anterior, and posterior views, ×1, adult paratype USNM 153004c; 26–30, ventral, dorsal, side, anterior, and posterior views, ×1, adult holotype USNM 153004d; 31–35, ventral, dorsal, side, anterior, and posterior views, ×1, adult paratype USNM 153004e; 36, dorsal view of shell broken to show spiralium (rotated to longitudinal position), ×1, paratype USNM 153004f; 37, ventrolateral view of shell broken to reveal part of spire held by siliceous partition in geopetal position, ×1, paratype USNM 153004g. [Hess Formation (Taylor Ranch Member), USNM 702e.]

Composita cracens, new species: 38–39, Exterior and interior views of pedicle valve, ×1, paratype USNM 153007g′; 40–41, exterior and interior views of pedicle valve with very deep muscle marks, ×1, paratype USNM 153007h′; 42–43, exterior and interior views of pedicle valve, ×1, paratype USNM 153007i′; 44–45, exterior and interior views of brachial valve, ×1, paratype USNM 153007j′; 46–47, exterior and interior views of brachial valve, ×1, paratype USNM 153007k′. [Bone Spring Formation, USNM 728f.]

48–52, Ventral, dorsal, side, posterior, and anterior views of adult shell, ×1, holotype USNM 153008a. [Bone Spring Formation, USNM 728e.]

PLATE 653.—Composita.

PLATE 654

Composita

Composita bucculenta, new species: 1–7, Ventral, dorsal, side, and posterior views, ×2, and dorsal, side, and anterior views, ×1, juvenile paratype USNM 153005a; 8–14, ventral, dorsal, side, and posterior views, ×2, and dorsal, side, and anterior views, ×1, young adult paratype USNM 153005b; 21–23, interior view, ×2, and exterior view, ×1, of pedicle valve, paratype USNM 153005c; 24–30, ventral, dorsal, side, and posterior views, ×2, and dorsal, side, and anterior views, ×1, adult paratype USNM 153005d; 31–37, ventral, dorsal, side, and posterior views, ×2, and dorsal, side, and anterior views, ×1, adult holotype USNM 153005e; 42–44, exterior view, ×1, and interior views, ×1, ×2, of brachial valve, paratype USNM 153005f. [Cathedral Mountain Formation (base), USNM 702ent.]

15–20, Ventral, anterior, and side views, ×2, and dorsal, side, and posterior views, ×1, adult paratype USNM 154548a; 38–39, interior views, ×1, ×2, of pedicle valve, paratype USNM 154548b; 40–41, interior views, ×1, ×2, of brachial valve, paratype USNM 154548c; 45–50, ventral, side, and interior views, ×2, and dorsal, side, and posterior views, ×1, adult paratype USNM 154548d; 51–56, ventral, side, and anterior views, ×2, and dorsal, side, and posterior views, ×1, adult paratype USNM 154548e; 57–62, ventral, side, and anterior views, ×2, and dorsal, side, and posterior views, ×1, adult paratype USNM 154548f; 63–68, ventral, side, and anterior views, ×2, and dorsal, side, and posterior views, ×1, adult paratype USNM 154548g. [Hess Formation, USNM 726n.]

Composita strongyle, new species: 69–73, Ventral, dorsal, side, anterior, and posterior views, ×1, juvenile paratype USNM 153038a; 74–78, ventral, dorsal, side, anterior, and posterior views, ×1, adult paratype USNM 153038b. [Neal Ranch Formation (bed 12 of P. B. King), USNM 701k.]

79–83, Dorsal, ventral, posterior, anterior, and side views, ×1, adult holotype USNM 153040a. [Neal Ranch Formation (beds 9–12 of P. B. King), USNM 701c.]

84–88, Ventral, dorsal, posterior, anterior, and side views, ×1, young adult paratype USNM 153041a. [Neal Ranch Formation, USNM 701.]

PLATE 654.—Composita.

PLATE 655

Composita

[All ×1]

Composita crassa, new species: 1–5, Ventral, dorsal, side, posterior, and anterior views, juvenile paratype USNM 153009a; 6–10, ventral, dorsal, side, posterior, and anterior views, juvenile paratype USNM 153009b; 11–15, ventral, dorsal, side, posterior, and anterior views, juvenile paratype USNM 153009c; 16–20, ventral, dorsal, side, posterior, and anterior views, young adult paratype USNM 153009d; 21–25, ventral, dorsal, side, posterior, and anterior views, adult paratype USNM 153009e; 26–30, ventral, dorsal, side, anterior, and posterior views, adult paratype USNM 153009f; 31–35, ventral, dorsal, side, posterior, and anterior views, adult holotype USNM 153009g; 36–37, interior and exterior views of brachial valve with hinge plate and cardinal process, paratype USNM 153009h; 38–39, interior and exterior views of brachial valve, showing end of cardinal process, paratype USNM 153009i. [Road Canyon Formation, USNM 719x.]

Composita emarginata Girty: 40–44, Ventral, dorsal, side, posterior, and anterior views of somewhat exfoliated shell, hypotype USNM 154545a; 47–51, ventral, dorsal, side, posterior, and anterior views of partly exfoliated shell, hypotype USNM 154545b. [Bell Canyon Formation (Lamar Member), USNM 738b.]

45–46, Exterior and interior views of brachial valve, hypotype USNM 154546a. [Bell Canyon Formation (Pinery Member), AMNH 537.]

PLATE 655.—Composita.

PLATE 656

Composita

[All ×1]

Composita discina, new species: 1–5, Ventral, dorsal, side, posterior, and anterior views, young adult paratype USNM 153010a; 6–10, ventral, dorsal, side, posterior, and anterior views, young adult paratype USNM 153010b; 11–15, ventral, dorsal, side, posterior, and anterior views, adult paratype USNM 153010c. [Skinner Ranch Formation, USNM 714p.]

16–20, Ventral, dorsal, side, posterior, and anterior views, adult holotype USNM 153013a. [Skinner Ranch Formation (base), USNM 708q.]

Composita enormis, new species: 21–25, Ventral, dorsal, posterior, side, and anterior views, juvenile paratype USNM 153020a; 26–30, ventral, dorsal, side, posterior, and anterior views, elongate juvenile paratype USNM 153020b; 31–35, ventral, dorsal, side, posterior, and anterior views, adult paratype USNM 153020c; 36–40, ventral, dorsal, side, posterior, and anterior views, adult holotype USNM 153020d; 43–47, ventral, dorsal, side, posterior, and anterior views, adult paratype USNM 153020e; 50–51, exterior and interior views of pedicle valve with pallial markings, paratype USNM 153020f. [Word Formation (lens between Willis Ranch and Appel Ranch members), USNM 706b.]

41–42, Ventral and dorsal views of crushed large shell, paratype USNM 154538a. [Word Formation (Appel Ranch Member), USNM 727j.]

48–49, Exterior and interior views of large brachial valve, paratype USNM 153021a. [Word Formation (Willis Ranch Member), USNM 706a.]

PLATE 656.—Composita.

PLATE 657

Composita

Composita pilula, new species: 1–5, Ventral, dorsal, side, posterior, and anterior views, ×1, juvenile paratype USNM 153027t; 6–10, ventral, dorsal, side, posterior, and anterior views, ×1, young adult paratype USNM 153027u; 11–15, ventral, dorsal, side, posterior, and anterior views, ×1, young adult paratype USNM 153027z; 38–39, exterior view, ×1, and interior view, ×2, of brachial valve with hinge plate and cardinal process, paratype USNM 153027c′. [Road Canyon Formation, USNM 720d.]

16–20, Ventral, dorsal, side, posterior, and anterior views, ×1, young adult paratype USNM 154539a; 21–25, ventral, dorsal, side, posterior, and anterior views, ×1, adult paratype USNM 154539b; 26–30, ventral, dorsal, side, posterior, and anterior views, ×1, adult paratype USNM 154539c; 31–35, ventral, dorsal, side, posterior, and anterior views, ×1, adult holotype USNM 154539d; 36–37, exterior and interior views of brachial valve, ×1, paratype USNM 154539e. [Road Canyon Formation, USNM 724j.]

Composita mexicana (Hall) [all hypotypes]: 40–46, Ventral, dorsal, side, anterior, and posterior views, ×2, and dorsal and side views, ×1, of young adult shell, USNM 154540a; 47–53, ventral, dorsal, side, posterior, and anterior views, ×2, and dorsal and side views, ×1, of adult shell, USNM 154540b; 54–59, ventral, dorsal, side, and anterior views, ×2, and dorsal and side views, ×1, of cracked shell, USNM 154540c; 60–62, exterior views, ×2, ×1, and interior view, ×2, of pedicle valve, USNM 154540d; 63–69, ventral, dorsal, side, posterior, and anterior views, ×2, and dorsal and side views, ×1, of adult shell, USNM 154540e; 70–72, exterior views, ×2, ×1, and interior view, ×2, of brachial valve with small bore hole, USNM 154540f; 73–75, exterior views, ×2, ×1, and interior view, ×2, of pedicle valve, USNM 154540g; 76–78, exterior views, ×2, ×1, and interior view, ×2, of pedicle valve, USNM 154540h; 79–81, exterior views, ×2, ×1, and interior view, ×2, of brachial valve, USNM 154540i. [Hueco Formation, USNM 725a.]

PLATE 657.—Composita.

PLATE 658

Composita

Composita imbricata, new species: 1–5, Ventral, dorsal, side, posterior, and anterior views, ×1, juvenile paratype USNM 153023a; 6–10, ventral, dorsal, side, posterior, and anterior views, ×1, juvenile paratype USNM 153023b; 11–15, ventral, dorsal, side, posterior, and anterior views, ×1, young adult paratype USNM 153023c; 16–20, ventral, dorsal, side, posterior, and anterior views, ×1, adult paratype USNM 153023d; 21–25, ventral, dorsal, side, posterior, and anterior views, ×1, adult paratype USNM 153023e; 32–36, ventral, dorsal, side, posterior (pedicle valve up), and anterior views, ×1, adult holotype USNM 153023f. [Cathedral Mountain Formation, USNM 702.]

26–30, Ventral, dorsal, side, posterior, and anterior views, ×1, adult paratype USNM 154541a. [Cathedral Mountain Formation (base), USNM 702un.]

31, Exterior view of brachial valve with color marks, ×1, paratype USNM 154542a. [Cathedral Mountain Formation (lower), USNM 721u.]

Composita nucella, new species: 37–43, Ventral, dorsal, side, posterior, and anterior views, ×2, and dorsal and side views, ×1, juvenile paratype USNM 153024a; 44–50, ventral, dorsal, side, posterior, and anterior views, ×2, and dorsal and side views, ×1, young adult paratype USNM 153024b; 51–57, ventral, dorsal, side, posterior, and anterior views, ×2, and dorsal and side views, ×1, adult holotype USNM 153024c; 58–62, ventral, dorsal, side, posterior, and anterior views, ×1, adult paratype USNM 153024d; 63–69, ventral, dorsal, side, posterior, and anterior views, ×1, ×2, adult paratype USNM 153024e; 70, side view of primary lamella and part of jugum, ×2, paratype USNM 153024f. [Bone Spring Formation (Cutoff Member), AMNH 678.]

PLATE 658.—Composita.

PLATE 659

Composita

Composita parasulcata, new species: 1–5, Ventral, dorsal, side, posterior, and anterior views, ×1, juvenile paratype USNM 153025r; 6–10, ventral, dorsal, side, posterior, and anterior views, ×1, juvenile paratype USNM 153025y; 11–15, ventral, dorsal, side, posterior, and anterior views, ×1, young adult paratype USNM 153025d′; 16–20, ventral, dorsal, side, posterior, and anterior views, ×1, young adult paratype USNM 153025e′; 21–25, ventral, dorsal, side, posterior, and anterior views, ×1, adult paratype USNM 153025j′; 33, ventral view of shell broken to show spiralium, ×2, paratype USNM 153025.f. [Word Formation (Willis Ranch Member), USNM 706e.]

26–32, Ventral, dorsal, side, posterior, and anterior views, ×2, and dorsal and side views ×1, paratype USNM 153026a; 45–51, ventral, dorsal, side, posterior, and anterior views, ×2, and dorsal and side views, ×1, adult paratype USNM 153026b. (Word Formation (China Tank Member), USNM 706c.]

34, 35, Exterior view, ×1, and interior view, ×2, of pedicle valve, paratype USNM 154543a; 36–37, exterior view, ×1, and interior view, ×2, of pedicle valve, paratype USNM 154543b; 38–44, ventral, dorsal, side, posterior, and anterior views, ×2, and dorsal and side views, ×1, adult paratype USNM 154543c; 52–53, exterior view, ×1, and interior view, ×2, of brachial valve, paratype USNM 154543d; 54–60, ventral, dorsal, side, posterior, and anterior views, ×2, and dorsal and side views, ×1, adult holotype USNM 154543e; 61–62, interior view, ×2, and exterior view, ×1, of brachial valve, paratype USNM 154543f; 63–69, ventral, dorsal, side, posterior, and anterior views, ×2, and dorsal and side views, ×1, adult paratype USNM 154543g. [Word Formation (lens between Willis Ranch and Appel Ranch members), USNM 706b.]

PLATE 659.—Composita.

PLATE 660

Composita

Composita pyriformis, new species: 1–6, Dorsal, side, posterior, and anterior views, ×2, and ventral and side views, ×1, adult paratype USNM 153030w; 26–31, dorsal, side, posterior, and anterior views, ×2, and ventral and side views, ×1, adult holotype USNM 153030x. [Bell Canyon Formation (Pinery Member), USNM 731.]

7–13, Ventral, dorsal, posterior, and side views, ×2, and dorsal, side, and anterior views, ×1, adult paratype USNM 153031a; 14–19, ventral, dorsal, and side views, ×2, and dorsal, side and anterior views, ×1, adult paratype USNM 153031b; 20–25, ventral, dorsal, and side views, ×2, and dorsal, side, and anterior views, ×1, adult paratype USNM 153031c. [Bell Canyon Formation (Pinery Member), USNM 725h.]

Composita prospera, new species: 32–36, Ventral, dorsal, side, posterior, and anterior views, ×1, young adult paratype USNM 153028t; 37–41, ventral, dorsal, side, anterior, and posterior views, ×1, adult paratype USNM 153028w; 42–46, ventral, dorsal, side, anterior, and posterior views, ×1, adult holotype USNM 153028x; 47–48, exterior and interior views of large brachial valve showing muscle marks, ×1, paratype USNM 153028f′; 49–50, exterior and interior views of large pedicle valve with distinct muscle marks, ×1, paratype USNM 153028g′. [Cherry Canyon Formation (Getaway Member), USNM 728.]

PLATE 660.—Composita.

PLATE 661

Composita

Composita quantilla, new species: 1–7, Ventral and dorsal views, ×1, ×2, and side, posterior, and anterior views, ×2, adult paratype USNM 153034v; 8–14, ventral and dorsal views, ×1, ×2, and side, posterior, and anterior views, ×2, adult holotype USNM 153034z; 15–21, ventral and dorsal views, ×1, ×2, and side, posterior, and anterior views, ×2, adult paratype USNM 153034y. [Road Canyon Formation, USNM 721x.]

Composita stalagmium, new species: 22–26, Ventral, dorsal, side, posterior, and anterior views, ×1, young adult paratype USNM 154344a; 29–33, ventral, dorsal, side, posterior, and anterior views, ×1, elongate adult paratype USNM 154544b; 36–40, ventral, dorsal, side, posterior, and anterior views, ×1, adult paratype USNM 154544c; 41–45, ventral, dorsal, side, posterior, and anterior views, ×1, adult paratype USNM 154544d; 46–50, ventral, dorsal, side, posterior, and anterior views, ×1, adult paratype USNM 154544e. [Road Canyon Formation, USNM 719x.]

27–28, Dorsal and side oblique views of broken shell with silicified spiralium, ×1, paratype USNM 153035a; 34, side view of broken shell with displaced jugum, ×1, paratype USNM 153035b; 35, dorsal view of broken shell with spiralium nearly intact, ×1, but rotated to longitudinal axis, paratype USNM 153035c. [Road Canyon Formation, USNM 702c.]

51–52, Side and dorsolateral views of broken shall with jugum and part of spiralium intact, ×2, paratype USNM 154547. [Road Canyon Formation, USNM 726z.]

PLATE 661.—Composita.

PLATE 662

Composita

[Figures 1–35 wide, specimens, 36–65 narrow; all ×1]

Composita stalagmium, new species: 1–5, Ventral, dorsal, side, posterior, and anterior views, juvenile paratype USNM 153035d; 6–10, ventral, dorsal, side, posterior, and anterior views, juvenile paratype USNM 153035e; 11–15, ventral, dorsal, side, posterior, and anterior views, juvenile paratype USNM 153035f; 16–20, ventral, dorsal, side, posterior, and anterior views, young adult paratype USNM 153035g; 21–25, ventral, dorsal, side, posterior, and anterior views, adult paratype USNM 153035h; 26–30, ventral, dorsal, side, posterior, and anterior views, adult paratype USNM 153035i; 31–35, ventral, dorsal, side, posterior, and anterior views, adult holotype USNM 153035j; 36–40, Ventral, dorsal, side, posterior, and anterior views, juvenile paratype USNM 153036a; 41–45, ventral, dorsal, side, posterior, and anterior views, juvenile paratype USNM 153036b; 46–50, ventral, dorsal, side, anterior, and posterior views, young adult paratype USNM 153036c; 51–55, ventral, dorsal, side, anterior, and posterior views, adult paratype USNM 153036d; 56–60, ventral, dorsal, side, anterior, and posterior views, young adult paratype USNM 153036e; 61–65, ventral, dorsal, side, posterior, and anterior views, large adult paratype USNM 153036f. [Road Canyon Formation, USNM 702c.]

PLATE 662.—Composita.

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Simple tabulations in the text (e.g., columns of data) may carry headings or not, but they should not contain rules. Formal tables must be submitted as pages separate from the text, and each table, no matter how large, should be pasted up as a single sheet of copy.

Use the metric system instead of, or in addition to, the English system.

Illustrations (line drawings, maps, photographs, shaded drawings) can be intermixed throughout the printed text. They will be termed Figures and should be numbered consecutively; however, if a group of figures is treated as a single figure, the components should be indicated by lowercase italic letters on the illustration, in the legend, and in text references: “Figure 9b.” If illustrations (usually tone photographs) are printed separately from the text as full pages on a different stock of paper, they will be termed Plates, and individual components should be lettered (Plate 9b) but may be numbered (Plate 9: figure 2). Never combine the numbering system of text illustrations with that of plate illustrations. Submit all legends on pages separate from the text and not attached to the artwork. An instruction booklet for the preparation of illustrations is available from the Press on request.

In the bibliography (usually called “Literature Cited”), spell out book, journal, and article titles, using initial caps with all words except minor terms such as “and, of, the” For capitalization of titles in foreign languages, follow the national practice of each language. Underscore (for italics) book and journal titles. Use the colon-parentheses system for volume, number, and page citations: “10(2):5-9.” Spell out such words as “figures,” “plates,” “pages.”

For free copies of his own paper, a Smithsonian author should indicate his requirements on “Form 36” (submitted to the Press with the manuscript). A non-Smithsonian author will receive 50 free copies; order forms for quantities above this amount with instructions for payment will be supplied when page proof is forwarded.