TROPICAL NORTH AMERICAN SPECIES OF PANICUM. By A. S. Hitchcock and Agnes Cha.se. INTRODUCTION. In a preceding paper1 our knowledge of the North American species of Panicum was presented in a revision of the genus, based upon mate- rial in the United States National Herbarium. Since the publication * of that paper a large amount of additional material from tropical North America has been accumulated. Mr. Hitchcock visited Mexico in 1910, Central America and Panama in 1911, and Jamaica and Trini- dad in 1912. Mrs. Chase visited Sonora in 1910 and Porto Rico in 1913. The collections of Mr. H. Pit tier in Panama, of Brother Le6n of the Colegio de la Salle, Habana, in Cuba, and of several other col- lectors in tropical North America, besides specimens from various islands of the West Indies received through Dr. I. Urban, serve to augment the amount of material studied. As a result of these further studies in the genus the range of nearly all the tropical species described in the revision can be presented in much greater detail. Several South American species hitherto unknown from North America and several new species have been discovered, while a few doubtful species and a few referred to synonymy have by field work and further study been established as valid. While the present paper is supplementary to the revision, it is designed to be of use for the region covered without necessarily referring to the main work. For this reason keys are given for all the tropical species, though descriptions are given of additional species only. A study in their native habitat of species before known from herbarium specimens alone, has necessitated in some cases a revision of the description of habit or of duration, or exceptions have been found to characters given as common for groups. Such notes are given without other description and are to be understood as additions to or corrections of the descriptions given in the revision. Following the reference to the original publication of each species is a reference 1 Contr. TJ. S. Nat. Herb. 10.1910. 459 460 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. to the description in the revision, if the species is there described. No synonymy is given except such as is additional to that cited in the previous work. The distribution here given is based upon all the material at present in the National Herbarium, including that already cited. As in the earlier paper all specimens cited are in the United States National Herbarium, unless otherwise stated. Specimens from other herbaria are cited when such specimens add to the known range. Through the courtesy of Dr. I. Urban the grasses of the Krug and Urban Herbarium in the Berlin Museum were submitted for study. Many additional specimens are cited from this herbarium, such specimens being indicated by the abbreviation UK. U. Herb." The range within the region covered is graphically presented by maps. For the sake of comparison these maps indicate also the distribution in the southern border of the United States of such, species as extend into this region. Trinidad and Tobago, though they are continental islands and their flora is essentially South American, are included in the West Indies because they are so included by Grisebach1 and by Urban.2 In order to connect Panama and Trinidad the detailed distribution.includes Venezuela and Colombia. KEY TO SPECIES ACT) GROUPS. Axis of branchlets produced beyond the base of the uppermost epikelet as a point or bristle 1 to 6 mm. long Subgenus Paurochaetii m, p. 463. Axis of branchlets not produced into a bristle. (In P. geminatum and P. pahidivagum the somewhat flattened axis pointed but not bristle-form.) Basal leaves usually distinctly different from those of the culm, forming a winter rosette; culms at first simple, the spikelets of the primary panicle not perfecting seed, later usually becoming much branched, the small second- ary panicles with cleistogamous, fruitful spikelets. Subgenus Dichanthelix'M, p. 512. Basal leaves pimilar to culm leaves, not forming a winter rosette; spikelets all fertile. Plants annual. Spikeleta piano-gibbous, the second glume swollen, bristly and burlike at maturity; first glume nearly as long as the minute spikelet. 116. P. hirtum. Spikeleta not piano-gibbous nor bur like. Panicles consisting of several more or less secund spikelike racemes; fruit transversely rugose; glumes and sterile lemma usually reticulate-veined See Fasciculata, p. 467. Panicles more or less diffuse (small and narrow in P. vas&janum). Blades ovate-lanceolate or elliptical, one-fifth to one-fourth as broad as long; plants low; spikeleta minute, not over 1.5 mm. long. Spikelets pyriform, attenuate at base, glabrous. 71. P. pyrularium. Spikelets elliptic, pubescent 67. P. trichoide»r 1 Fl. Brit. W. Ind 2 Symb. Ant HITQHOOOK AND CHASE—TROPICAL NORTH AMERICAN PANICXJM. 461 Blades linear, many times as long as broad; spikelets 1.7 mm. or more long. First glume not over one-fourth the length of the spikelet, truncate or triangular-tipped. See Dichotomifloha, p. 473. First glume usually as much as half the length of the spike- let, acute or acuminate See Catillaria, p. 476. Plants perennial. Spikelets short-pediceled along one side of the panicle branches, forming more or lew spikelike racemes. First glume nearly as long as the obtuse spikelets; plants with long wiry stolons with woolly nodes 111. P. obtusum. First glume much shorter than the spikelet. Spikelets more or less hispid. Sterile lemma glandless; second glume inflated-gibbous. 73, P. ineptum. Sterile lemma bearing a pair of crateriform glands. - See Stolonifera, p. 500. Spikelets glabrous. Blades lanceolate or ovate-lanceolate; glumes strongly carinate. See Stolonifera, p. 500. Blades linear, often elongated; glumes not carinate or but slightly so. Fruit transversely rugose See Geminata, p. 466. Fruit not rugose. Second glume shorter than the spikelet; fertile lemma subin- durate, inrolled only at base, scabrous at the acute apex. 112. P. stagnatUe. Second glume as long as the spikelet; fertile lemma indurate, inrolled to the summit See Laxa, p. 492. Spikelets in open or sometimes in contracted or congested panicles, but not in 1-sided spikelike racemes. Fruit transversely rugose See Maxima, p. 433. Fruit not transversely rugose (minutely papillose-roughened in P. millegrana). Culms more or less succulent; plants glabrous or nearly so throughout, aquatic or eubaquatic. First glume not over one-fifth the length of the spikelet. See Dichotomifloba, p. 473. First glume one-third to half the length of the spikelet. Fruit indurate, the margins of the lemma inrolled; culms erect; panicle contracted 48. P. eonden&um. Fruit subindurate, the margins of the lemma inrolled only at base; culms decumbent at base; panicles open. Spikelets 1.8 mm. long; second glume shorter than the fruit; secondary panicle branches secund 112. P. stagnatUe. Spikelets 2.5 mm. long; second glume exceeding the fruit; panicle branches not secund 113. P. grande. Culms not succulent. First glume hyaline, inconspicuous; spikelets acuminate; lower blades with long petiole-like bases 114. P. tuerckheimii. First glume evident. First glume very small, not over one-fourth the length of the small obovate, blunt, glabrous spikelets. See Pabviglumia, p. 502. 462 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM First glume usually more than one-third the length of the spikelet, if shorter the spikelets not small and blunt. Sterile palea enlarged and indurate at maturity, expanding the spikelet; blades scarcely wider than their sheaths. See Lax a, p. 492. Sterile palea if present not enlarged and indurate. First glume short, blunt; spikelets pointed; base of culm usually decumbent and rooting. See Dichotomwlora, p. 473. First glume usually more than one-third the length of the spikelet. Plants forming conspicuous hard creeping scaly roots tocks. See Vibgata, p. 486. Plants not forming creeping scaly rootstocks. Fruit crested at the apex; spikelets 5.5 to 6 mm. long. 115. P. zizanioides. Fruit not crested. Panicles narrow and few-flowered; culms erect and wiry; blades drying involute.. See Tenera, p. 490. Panicles open or contracted, many-flowered. Panicles 40 to 60 cm. long, the numerous elongated branches in verticils 77. P. megi&ton. Panicles mostly much lesa than 40 cm. long; branches not verticillate. Spikelets ehort-pediceled along the nearly simple panicle branches 48. P, condenwm. Spikelets long-pediceled; panicle open at maturity. Primary panicles open, the secondary reduced, narrow, partly inclosed in the sheaths. First glume three-fourths as long as the ellipti- cal spikelets; fruit apiculate. See Cokdovensia, p. 525. First glume one-third as long as the pyriform spikelets; fruit not apiculate. 104. P. nodalum. Primary and secondary panicles alike, or the secondary wanting. First glume not pointed, two-thirds the length of the spikelet or more; spikelets blunt. Panicles not over 6 cm. long; plants some- what glaucous, relatively small. See Parvifolia, p. 506. Panicles 10 to 20 cm. long, very diffuse; plants tall, not glaucous. Spikelets viscid, 3 mm. long. 75. P. glutinomm. Spikelets not viscid, 2 to 2.3 mm. long. 74. P. mUUgrana. First glume pointed, usually less than two- thirds as long as the pointed spikelets. Spikelets more or less pubescent. Culms slender, straggling; spikelets not turgid; glumes and sterile lemma hir- sute along the margins. 72. P. haenkeanum. HITCHCOCK AND CHASE—TROPICAL NORTH AMERICAN PANICUM. 463 Culms stout, erect or nearly go; spikelets turgid, sparsely hirsute. 76. P. rudgei. Spikelets glabrous. Culms straggling; spikelets minute. 68. P. trichanthum. Culms erect or stiffly ascending; blades linear, usually elongated. Sheaths glabrous; culms 1.5 to 2 meters high 40. P. icknatrihoidet. Sheaths hirsute, or if glabrous the culms less than 1 meter high. See Diffusa, p. 480. ANNOTATED LIST OF THE SPECIES. Submenus PAXTROCHAETIUIC Hitchc. & Chase. Blades less than 10 cm. long, not narrowed toward the base; spikelets about 2.5 mm. long 4. P. ramisetum. Blades elongated, usually more than 15 cm. long, narrowed toward the base. First glume rounded or truncate; second glume about as long as fruit 3. P. ckapmani. First glume acute; second glume about two-thirds as long as fruit. Spikelets 1.5 mm. long; blades involute 1. P. distantijlorum,. Spikelets 2 mm. long; blades flat 2. P. utouxmaeum. 1. Panicum distantijlorum A. Rich, Panicum distantijlorum, A. Rich, in Sagra, Hist. Cuba 11:304.1850; Contr. U. 8. Nat. Herb. 10: 23.1910. DISTRIBUTION. limestone hills at low altitudes, Bahamas to Cuba and Haiti; Curasao. The type specimen from Cuba. m 13 I i Vv K / / V 1 . T" i fVJ \J / f ^ v. • n \ V C -\L^r\ ] , f , ^ i / [jf i - ^ t f ^ V n 4 {A v .r^ Fig. 11.—Distribution of P. iutaniiflorum. Santo Domingo: Naranjo, FuerU» 1284. Los Ch&rcos, Fuertes 1427. Curasao: BrUton & Shafer 3088. Bonaire, Suringar in 1885. (E. U. Herb,)1 Bahamas: Inagua, Hitchcock in 1890, Nash & Taylor 893 (both Field Mus. Herb.). Cuba: Play a de Cojimar, Hitchcock 144, Le6n 912. Near Habana, Le6n305b,567,2382. Santiago, Le6n917. SilladeCayo, Shafer 2512. Guanoroca, Wright 284. Han6bana, Wright 285. Playa de Marianao, Le6n in 1909. Without locality, Wright 3452. 1 Krug & Urban Herbarium * 464 CONTRIBUTIONS FROM THE NATIONAL HEBBARIUM. 2. Panicum utowanaeum Scribn Panicum utowanaeum Scribn. in Millsp. Field Mus. Bot. 2: 25.1900; Contr. TJ. S. Nat. Herb. 16: 24.1910. DISTRIBUTION. Open rocky soil, mostly near the coast, Cuba, Porto Rico, Guadeloupe, and Vene- zuela. The type specimen from Porto Rico. Cuba: Triscomia, Hitchcock 141, Tracy 9089. Cayo Guajaba, Shafer 2830. Playa Marianao, Wilson 9497. Eastern Cuba, Wright 3452. Santo Domingo: Azua, Rose, Fitch & Russell 3891. Porto Rico: Guanica, Mills paugh PI. XJtow. 702, Sintenis 3365, 3416, 3463, Chase 6520. Santa Rita, Chase 6535, LagunaGuanica, CAose6533. Mona, Hess 431, 455, 457. FiO. 12.—Distribution of P. utowanaeuni. Leeward Islands: Guadeloupe, Dtiss 3177. Venezuela: Near Puerto Caballo, Pittier 6434. 3. Panicum chapmani Vaecv. Panicurn chapmani Vaaey, Bull. Tor- rey Club 11: 61. 1884; Contr. U. S, Nat. Herb. IB: 24.1910. distribution. Coral sand and shell mounds, south- ern Florida and the Bahamas. The type specimen from Florida. Bahamas: New Providence, Brit- ton de Brace 401. Rose la- land, Britton & Milhpaugh Fig. 13.—Distribution of P. chapmani. 2137. Great Exuma, Britton & Mills paugh 3076. (All in Field Herb.) 4. Panicum ramisetum Scribn. Mus. Panicum ramisetum Scribn. TJ. S. Dept. Agr. Div. Agrost. Circ. 27: 9.1900; Contr. TJ. 8. Nat. Herb. 16: 25. 1910. distribution. Fit}. 14.—Distribution of P. ramitetttm. Sandy plains and prairies, southern Texas and northern Mexico. The type specimen from Texas. Coahuila: Near Dfaz,1 Pringle 8323. 1 The "Gu£a Postal de la Reptiblica Mexicans " has been followed in the accent- ing of Mexican geographical names. HITCHCOCK AND CHASE—TROPICAL NORTH AMERICAN PANICUM. 465 TRUE PANICUM. GEM IN ATA. Nodes bearded 7. P. barbinode. Nodes glabrous. Spikelets 3 mm. long; glumes and sterile lemma papery 6. P. paludivagum. Spikelets not over 2.4 mm. long; glumes and sterile lemma not papery 5. P. geminatum. 5. P&nicum geminatum Forsk. Panicum geminatum Forsk. Fl. Aegypt, Arab. 18. 1775; Contr. U. S. Nat. Herb. 16: 30.1910. This species is described by Presl1 under the name Panicum brizoides L. (as well as under P. brizaeforme Presl). The Haenke specimen from Mexico is in the herb- arium of the National Museum at Prague. t DISTRIBUTION. Moist ground, ditches and swamps, mostly near the coast, tropical regions of both hemispheres, in America extending north into southern Florida and Texas. Origi- nally described from Kosetta, Egypt. Lower California : El Taste, Brandegee in 1893. San Jos6 del Cabo, Brandegee 14, 36. Sonoba : Yaqui River, Palmer 15 in 1869. Guaymas, Palmer 690 in 1887. Sierra de Alamos, Hose, Standley & Russell 12996. Sinaloa: Mazatlin, Rose, Standley Russell 14109. Tamaulifas: Tampico, Hitchcock 5796, Palmer 259 in 1910, Colima : Manzanillo, Hitchcock 7032. Veracruz; Veracruz, Hitchcock 6586. Guerrero: Acapulco, Palmer 289 in 1894. YucatAn: Izamal, Gaumer 1027. Guatemala: San Jos£, Kelltrman 6250. Salvador: Lake llopango,' Hitch- cock 8920. Cobta Rica: Bebedero, Jimbiez 734. PANAMA: Corozal, Pittier 2168, 2170. Pedro Miguel, Hitch- cock 7956, Pittier 2509. Em- pire, Pittier 3714. Gatun, Hitchcock 7980. Bahamas: Nassau, Curtiss 175. Fortune Island, Eggers 3992 (K. U. Herb.). Cuba: Qabana, Le6n 769,918. CorrientesBay, Britton , Fig. 45.—Distribution of QMexbrryhtii. dura, Tracy 9068. Santiago de laa Vegaa, Traci/ 9116. La Perla, Le6n 3783, El Calvario, Le6n 922, 2674. Guayabal, Lc6n 922b. Without locality, Wright 758. Eastern Cuba, Wright. Santiago de Cuba, Le6n 3747. Porto Ilico: Coamo Springs, Chase. 0517. Cayey, Chase 6744, Tabucoa, Sintam 4983. Leeward Islands: Guadeloupe, Dims 3184. Antigua, Wullschlaegel 620, 621. (K. U. Herb ). Colombia: SantaMarta, Smith 165. 33. Panicum hirsutum Swartz. Panicum hirsutum. Swartz, Fl. Ind. Gee. 1: 173. 1797; Contr. U. S. Nat. Herb. 15: 77, 1910. Panicum datum Willd.; Steud. Nom. Bot. cd. 2. 2: 256.1841. In the Willdenow I Herbarium this unpublished name is written on a Humboldt collection from "America merid. *' The sheathe, especially the lower, of thia robust species are hirsute with spreading stiff hairs that cause mechanical irritation to the skin. The panicles are at first com- pact, with ascending branches, but become diffuse at maturity, the branches finally widely spreading. distribution. Open moist mil, West Indies and central Mexico to northern South America. The type specimen from Jamaica. Colima: Manzanillo, Hitchcock 7031. Oaxaca: San Antonio, PringU 5573. Costa Rica: Port Limon, Hitchcock 8435. Along Hananitu River, Pittier 3634. Zent Farm, Pittier in 1904, Tonduz 266. Puerto Viejo, Biollcy 7467. Costa Rica: San Jose, Hitchcock 8452. Guanacaate, Jimenez 730, Llano Grande de Puriscal, Jimenez 880. Nuestro Amo, Jimenez530. Salinas Bay, Pittier 2633, Tonduz 2858. Panama: South of David, Hitchcock 8377. Balboa, Hitchcock 7997, 8014. Taboga Island, Hitchcock 8065, 8094. Bahamas: Crooked Island, Brace4812. <' i ba : La Soledad, Eggers 5406. Ilerra- + HITCHCOCK AND CHASE TROPICAL NORTH AMERICAN PANICUM. 483 Fig. 46.—Distribution of P. htrmtum* Panama: Between Bohfo and Frijoles, Hitchcock 8397. Near Bohio, Hitchcock 8392, Tabernilla, Hitchcock 8382. Gorgona, Amer. Gr. Nat. Herb. 37. Pedro Miguel, Hitchcock 7957. Puerto Obaldfa,Pittier 4374. Culebra, Pittier 3441. Cuba: Matanzaa, Wright in 1865. GuanUnamo, Le&n 3913. Leeward Islands: Guadeloupe, Dms 3917. Windward Islands: Martinique, Buss 768 (K. U. Herb.). Trinidad: St. Margaritas, Brood- way 2629. "Burke's pasture,'' Bot. Gard. Herb. 2295. Venezuela: Rfo Grande del Tuy, Paparo, Pittier 6332. Boburee, John 353, 355. Colombia: Santa Marta, Smith 164. MAXIMA. Culms with a cormlike base. Blades mostly over 5 mm. wide; culms more than 1 meter high 36. P. bulbosum. Blades less than 5 mm. wide; culms rarely as much as 1 meter high 36a. P. bulbosun sdaphilum. Culms from a creeping rootstock, not cormlike at base. Nodes hirsute; ligules 4 to 6 mm. long; fruit strongly rugose 34. P. maximum. Nodes glabrous; ligules 2 mm, long; fruit very obscurely rugose 35. P. plenum. 34. Panicum maximum Jacq. Panicum maximum Jacq. Coll. Bot. 1:76.1786; Contr. U. S. Nat. Herb. 16:78.1910. DISTRIBUTION. Open ground, at low altitudes, escaped from cultivation, southern Florida through Mexico and West Indies to South America, a native of Africa and now widespread in the warmer parts of the Old World. Type locality, Guadeloupe. Sinaloa: Mazatldn, Rose, Standley & Russell 14121. Co LIMA: Paso del Rfo, Emrick 3. Veracruz: C6rdoba, Hitchcock 6410, Finck 8, Kerber 48. Jalapa, Hitchcock 6621, Huitamalco, Liebmann 425 T3 1 in part. Veracruz, Hitchcock 6562. San Francisco, Smith 1409. Zacu- ■ apdn, Purpus 3774. YucatAk: Izamal, Gaumer 719. British Honduras: Manatee Lagoon, Peck 195 (Gray Herb.). Guatemala: Escuintla, Smith 2705, 2706, Hitchcock 9001. Morales, Kel- lerman 6267. Gualtln, Deam. 6268. Finca Sepacuit£, Alta Verapaz, Cook & Griggs 579. Honduras: Puerto Cortez, Kellerman 4725. Salvador: San Salvador, Velasco 2. Izalco, Pittier 1960. Without locality, Renson 293. Fig. 47.—Distribution of P. maximum. 484 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. Nicaragua: Corinto, Hitchcock 8702. Costa Rica: Zent Farm, Pittier in 1904. Boca Banana, Tonduz 9114. San Joe£, Pittier 9050. Nuestro Amo, Pittier 2034, 16662. Alajuelita, Tonduz 2995. Panama: Taboga Island, Hitchcock 8080. Cafia, Williams 779. Culebra, Pittier 2088, 4806, Amer. Gr. Nat. Herb. 38. Bermuda: North Shore Road, Brown & Britton 20, Ifarshberger in 1905. Bahamas: Nassau, Curtiss 124. Eleuthera, Geogr. Soc. Baltimore 338. Cuba: Herradura, Hitchcock 156. Guines, Leon 427, Liebmann 445. Santiago de las Vegas, Baker 32, Wilson 438, Hitchcock 157. Santiago de Cuba, Le6n 915, Pollard 6c Palmer 283. Guayabal, Le&n 921. Marianao, Le6n 957. Guana- jay, Palmer & Riley 816. San Diego de log Bafios, Palmer & Riley 542, 545. El Guama, Palmer & Riley 178. Pinar del Rfo, Palmer & Riley 377. Sierra de Anafe, Le6n 2871. Jamaica: Port Antonio, Fredholm 3319. Kingston, Hitchcock 9256, and in 1890, Gordon Town, Hart 797. Hope Gardens, Harris 11249. Haiti: Gonai'ves, Buck 468 (K. U. Herb.). Santo Domingo: Azua, Rose, Fitch & Russell 3949. San Pedro de Macoris, Rose, Fitch & Russell 4172. Porto Rico: Guanica, Sintenis3366. Mayaguez, Sintenis 51, Chase 6256. Cayey, Sintenis 2468. Aibonito, Chase 6332. Sobrante, Eggers 1226. Martin Pefla, Heller 377. Vieques, Chase 6669. Mona, Hess 449. Danish West Indies: St. Croix, Ricksecher 200, 413. St. Thomas, Millspaugh 454, Eggers in 1887, Rose 3184. Leeward Islands: Antigua, WuUschlaegel 623b, Rose, Fitch & Russell 3452. Dominica, Jones 10. Guadeloupe, Duss 3186. St. Bartholomew, Goes (K. U. Herb.). Saba, Boldingh 1580, Suringar in 1885 (both in K. U. Herb.) Windward Islands: Martinique, Duss 1288. Barbados, Dash 259. Grenada, Broadway in 1905. St. Vincent, Smith & Smith 288 (K. 0. Herb.). Trinidad: Four Roads, Hitchcock 10049. Tobago: Scarborough, Broadway 4081. Plymouth, Hitchcock 10239. Venezuela: Caracas, Pittier 6163. Around Dos Caminos and Los Chorros, Pittier 5917. Rio Grande del Tuy, Pittier 6327. Island of Margarita, Miller & Johnston 177. Colombia: Santa Marta, Smith 2153. Cartagena, Hitchcock 9917. Rfo Frfo, Pittier 1617. 35. Panicum plenum Hitchc. & Chase. Panicum plenum Hitchc. & Chase, Contr. U. S. Nat.. Herb. 16: 80. 1910. Moist places in rocky hills and canyons, southwestern United Statos to central Mexico. The type specimen from New Mexico. Chihuahua: Santa Eulalia Plains, So nora: Las Cuevas, Hartman 170. Hitchcock 7772. Wilkinson in 1885. Chihuahua, DISTRIBUTION Fig. 48.—Distribution of P. plenum. Coahuila: Saltillo, Hitchcock 5609. Veracruz: Orizaba, Botteri 160. Durango: Durango, Painter 741 in 1896. Jaral, Schumann 1733. J HITCHCOCK AND CHASE—TROPICAL NORTH AMERICAN PANICUM. 485 36. P&nicum bulbosum H. B. K. Panicum bulbosum H. B. K. Nov. Gen. & Sp. 1: 99.1816; Contr. U. S. Nat. Herb. 15: 81. 1910. DISTRIBUTION. Moist places in canyons and valleys, southwestern United States to southern Mexico. The type specimen from central Mexico. Chihuahua: Candelaria, Stearns 2C6. Chihuahua, Pringle 377. Colonia Garcia, Nelson 6187, Tovmsend 6c Barber 221. Sierra Madre, Nelson 6301. Mount Mohinora, Nelson 4901. Canon de San Diego, Hartman 790. Durango: Otfriapa, Palmer 340 in 1906. Durango, Palmer 525a in 1896, With- out locality, Palmer 741 in 1896. Tepic : Between Aguacate and Dolores, Rose 3361. Between Pedro Paulo and San Blasito, Rose 1999. San Luis PotosI: San Luis Potosf, Parry & Palmer 958. Las Canoas, Hitchcock 5754. Jausco : Road between Mexquitic and Monte Escobedo, Rose 2609. Ne- vada de Colima, Hitchcock 7150. Rfo Blanco, Palmer 207 in 1886. MichoacAn: Morelia, Arsbie in 1909. Mexico: Federal District, Orcutt 3518, Hitchcock 5932, 5941, 7835, Amer. Gr. Nat. Ilerb. 39, Holway 12, Bourgeau 235, Rose HITCHCOCK AND CHASE—TROPICAL NORTH AMERICAN PANICUM. 487 38. Panicum gouini Fourn. Panicum gouini Fourn. Mex. PI, 2: 28. 1886; Contr. U. S. Nat. Herb. 15:86.1910. DISTRIBUTION. Sea beaches along the Gull of Mexico. The type specimen from Veracruz. Veracruz: Veracruz, Pringle 5569, Amer, Gr, Nat. Herb. 40, Miiller 2177. Antigua, Liebmann 450. Coatzacoalcos, Smith 913. Fia. 52.—Distribution of P. gouini. 39. Panicum virgatum L. Panicum virgatum L. Sp. PI. 59. 1753; Contr. TJ. S. Nat. Herb. 15: 87.1910. distribution. Prairies and open woods, eastern and central United States, south to north- ern South America. The type speci- men from Virginia. Jausco: Rio Blanco, Palmer 207 and 510 in 1886. Chiapas: Between San Kicardo Fig. 63.—Distribution of P. virgatum. an^ Ocozucuantla, Nelson 2975. Honduras: Santa Anna, Thieme 532. Venezuela: Alto A pure, John 198. Colombia: Santa Marta, Smith lfitt. / 39a. Panicum virg&tum cubense Grieeb. Panicum virgatum cubense Grisob. Cat. PI. Cub. 233. 1866; Contr. U. S. Nat. Herb. 16: 92. 1910. " f-j | ] f distribution. Pine woods, Atlantic Coastal Plain, Bermuda and Cuba. The type speci- men from Cuba. Bermuda: Stone in 1888 (Acad. Phil. Herb.). Cuba: Bataban6, IlitchcocJc 153, Palmer & Riley 1134. Be- Ffo. 54.—Distribution of P. virgatum cxtben&t. twecn Laguna Jovero and Laguiia Herradura, Sha/er 10927. Without locality, Wright 3873. 488 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 40. Panieum ichnanthoides Fourn. Panieum ichnanikoides Fourn. Mex. PI. 2: 30.1886; Contr. U. S. Nat. Herb. 15: 88. 1910, as synonym under P. virgatum,, The type specimen, Miiller 2002, in the her- barium of the Botanical Garden in St. Petersburg, was collected at Orizaba. Panieum buchingeri Fourn. Mex. PI. 2: 30. 1886. ''Orizaba (Thomas in herb. Buchinger)." Contr. U. S. Nat. Herb. 16: 329: 1910. We have been unable to find the type. From the description it ia evident that the species is allied to P. virgatum L., while the locality would indicate P. ichnanthoides. DESCRIPTION. Plants in largo clumps with knotted crowns, without creeping rootstocks; culms 1.5 to 2 meters high, erect or decumbent at base, smooth, firm, and hard, more or less glaucous about the nodes; sheaths shorter than the inter- nodes, pubescent on the overlapping margin toward the apex, otherwise glabrous; liguleabout3 mm. long, mem- branaceous-ciliate; blades elongate, mostly 8 to 15 mm. wide, flat except at the narrowed and usually inrolled base, scabrous on the margins, villous on the upper surface near the base, otherwise glabrous; panicle 20 to 40 em. long, one-fourth to one-third as wide, the long slender branches ascending; spikelets 3.5 to 4.2 mm. long, about 1.5 mm. wide, similar to those of P. virgatum. This species is closely allied to P. virgatum L., from which it differs in the absence of creeping rootstocks and in the narrow panicle. The patch of plants from which was collected Hitchcock's no. 6364 is probably that from which Botteii, Miiller, and Thomas obtained their specimens. This patch lies along a trail leading up a prominent hill at tho western edge of the city of Orizaba, a locality likely to be visited by all botanists collecting in that region. DISTRIBUTION. Open rocky hillsides, southern Mex- ico, British Honduras, and Nicaragua. Puebla: Tehuac&n, Endlick 1938. Veracruz: Orizaba, Botteri 648, Hitchcock 6364, Mii ller 2002. British Honduras: Manatee La- goon, Peck 73 (Gray Herb.). Nicaragua: Jinotepe, Hitchcock 8685. Pig, 56.—Distribution of P. ichiunUhoid(3. Fig. 55.—P. ichnanthoides. From type specimen. 41. Panieum altum sp. nov. description. Plants perennial, in tangled masses, the culms decumbent and straggling at baee stout, reedlike, as much as 6 mm. in diameter, ascending to a height of 2 to 4 meters, smooth and glaucous, simple or with extra vaginal, mostly erect, sterile branches from the swollen nodes; sheaths smooth; ligule a short membrane less than 1 mm. long, the ciliate fringe once or twice as long; blades flat, firm, not greatly elongated, mostly 30 to 45 cm. long, 8 to 15 mm. wide, smooth except the scabrous margins, panicles rather more densely flowered than in P. virgatum, 20 to 30 cm. long, narrowly ovoid in out- HITCHCOCK AND CHASE—TROPICAL ItOBTH AMERICAN PANICUM. 489 Fig. 57,—P. altum. From type specimen. line, open, the slender scabrous branches ascending and spreading, fascicled, some naked at base, with short branchlets intermixed; spikelets rather short-pediceled, 3.2 to 4 mm. long, about 1.2 mm. wide, turgid, glabrous, the glumes and sterile lemma strongly nerved, pointed, somewhat keeled, usually widely gaping, the first glume about two-tliirds the length of the spikelet, the second glume and sterile lemma exceeding the fruit, subequal; fruit 2 to 2.2 mm. long, 1 mm. wide, elliptic. • Type in the U. S. National Herbarium, no. 093326, collected in moist sandy soil, near sea beach on Point Cham6, Province of Panama, September 18,1911, by A. S. Hitchcock (no. 8167), In the inflorescence this species closely resembles P. virgatum, but in habit it differs distinctly. It grows in masses like large reeds such as Phragmites but is straggling and much tangled at base. DISTRIBUTION. Sandy marshes or flats near the seacoast, British Honduras to Trinidad. British Honduras: Manatee Lagoon, Peck 123 (Gray Herb.), Costarica: Buenos Aires, Ton<2«z3619. Panama: Point Cham£, Bitchcock 8167. Trinidad: Near Port of Spain, Bitch- cock 10053. Icacos, Hitchcock 10154. Three miles south of Cedros, Bitch- cock 10159. Tobago: Plymouth, Bitchcock 10233. Fig. 58.—Distribution of P. aitum. Pigeon Point. Broadway 3068. 42. Panicum havardii Vasey. Panicum havardii Vasey, Bull. Torrey Club 14: 95.1887; Contr. U. S. Nat. Herb. 15: 93.1910. DISTRIBUTION. Arroyos and sand hills, southwestern United States and northern Mexico. The type specimen from Texas. Chihuahua: Paso del Norte (Ju&rez), Pringle 1124. rio. 59—Distribution of P. havardii. 43. Panicum amarulum Qitchc. & Chase. Panicum amarulum Hitchc. & Chase, Contr. U. S. Nat. Herb. 16: 96.1910. DISTRIBUTION. Sandy seashores and coast dunes, *" southeastern United States, Bahamas, and Cuba. The type specimen from Virginia. Bahamas: Great Bahama, Britton & Millspaugh 2739. New Providence, Britton & Brace 307,403 (all FieldMus. Herb ). Cuba: Camaguey, Shafer 2735. Fig, 60,—Distribution of Pr amarulumt 490 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. TENERA. Second glume and sterile lemma exceeding the fruit; spikelets pointed 44. P. tenerum. Second glume and sterile lemma not exceeding the fruit; epikeleta rather blunt. Pedicels bearing long stiff erect haira at the summit 46. P. caricoides. Pedicels not hairv. Spikelets attenuate at base, alxrnt 2 mm. long; leaves more , or less pilose 45. P. sienodoides. Spikelets not attenuate at base, about 1.5 mm. long; leaves glabrous 47. P. stenodes. 44. Panicum tenerum Beyr. Panicum tenerum Beyr. in Trin. M£m. Acad. St. P6tersb. VI. S< i. Nat. 1: 341. 1834; Contr. U. S. Nat. Ilerb. 15: 97. 1910. DISTRIBUTION. Fig. fil.—Distribution of JJ, tcnerurti* Margins of sandy swamps and ponds and in wet places in sandy woods, southeastern United States, Cuba, and Porto Rico. The type specimen from Georgia. Cuba: Herradura, Hitchcoch 154, Tracy 9080. Laguna Jovero, Shafer 10750. Laguna Los Indios, Shafer 10807. Pinar del Rio, Wright 3870 in part. Porto Rico : ("ampo Alegre, Chase 6617. 45. Panicum stenodoides Hubbard, Panicum stenodoides Ilubbard, Proc. Amer. Acad. 40: 497. 1913. "Type (in the Gray Herb.) and only specimen seen, low pine ridge, Ycacos Lagoon, March 5,1907, M. E. Peck, no. 681." A portion of the type in Ilubbard's herbarium has been examined. DESCRIPTION. Plants perennial in dense tufts; culms erect, slender and wiry, glabrous or sparsely pilose below the glabrous nodes, 20 to 40 cm. high, producing from the upper nodes slender leafless panicle-bearing branches; sheaths papillose or more or less papillose-pilose, the lowermost bladeless, glabrous, in age fibrous; ligule membranaceous, about 0.3 mm. long; blades erect, flat at base, involute toward the apex, 3 to 8 cm. long, 1 to 2 mm. wide, more or less papil- lose or papillose-pilose, at least on the upper surface, some- times glabrous; panicles short-exserted, usually exceeded by the uppermost blade, about 1 cm. long, narrow, bearing 3 to 7 spikelets on appressed scabrous pedicels, rarely a few delicate hairs at the apex of the pedicels; spikelets 2 to 2.1 mm. long, 0.9 mm. wide, turgid, attenuate at base, glab- rous; first glume about half as long as the spikelet; second glume and sterile lemma subequal, barely covering the fruit, strongly nerved; fruit 1.7 min. long, 0.8 mm. wide. Fig. t>2.—P. stenodoidesr From typo specimen. HITCHCOCK AND CHASE—TROPICAL NORTH AMERICAN PANICUM. 401 This species resembles P, stenodes, but differs in having larger spikelets and papil- lose-pilose or at least papillose sheaths. The type specimen and Hitchcock's no. 8147 are conspicuously pilose on sheaths and blades, but the other specimens of this little-known species are papillose only or have a few hairs on the upper surface of the blades. DISTRIBUTION. Open grass land and moist savannas, Central America and northern South America. British Honduras: Ycacos La- goon, Peck 681 (Gray Herb.). Costa Rica: Buenos Aires, Tonduz 3583. Panama: Chorrera, Hitchcock 8147. Near Corozal, Hitchcock 9207. Fig. 63.—Distribution of P. stenodoidet. Trinidad: Piarco Savanna, south of Arouca, Hitchcock 1C346. 46. Panicum caricoides Nees. Panicum caricoides Nees; Trin. Gram. Pan. 149.1826. Trinius received the type specimen from Nees, "V. spp. Brazil. (N. ab Esenb.)" Nees 1 afterwards describes the species more fully and gives the original locality as "provincia Paraensi." The type specimen is in the Trinius Herbarium at the St. Petersburg Academy of Science. It is evidently a portion of the specimen at the Munich Herbarium. This specimen, which is the basis of Nees's later description, was collected in Pard by Martius. Panicum junciforme Steud. Syn. PI. Glum. 1: 82. 1864. Given as a synonym of P. caricoides. description. Perennial, in tufts; culms erect, slender, glabrous, stiff and wiry, as much as 90 cm. high; sheaths smooth; ligule membranaceous, lacerate, minute; blades appressed, nar- rower than the sheath, involute, glabrous, 1 to 5 cm. long, the lower rarely longer; panicles terminal and axillary from the upper sheaths, short-exBerted, 1 to 1.5 cm. long, narrow, nearly simple, the later panicles smaller, in fascicles of 2 or 3, at first partially inclosed by the somewhat inflated sheaths, the pedicles bearing long erect white hairs just below the rather crowded spikelets; spikelets 1.5 to 1.8 mm. long, about 0.8 mm. wide, turgid, glabrous; first glume about half as long as the spikelet, subacute; second glume and sterile lemma equal, covering the fruit, strongly nerved; fruit 1.4 to 1.5 mm. long, 0.6 mm. wide. distribution. Wet savannas, Trinidad to Brazil. Trinidad: Aripo Savanna, Cumuto Station, Ilitchcork 10069. J-'iq. 65.—Distribution of P. caricoides. Fig. 64.—P. caricoides. From type specimen. 'Agrost. Bras. 108. 1829. 492 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 47. Panicum stdnodes Griseb. Panicum stenodes Griseb. Fl. Brit. \V. Ind. 547. 1864; Contr. U. S. Nat. Herb. 15: 98.1910. DISTRIBUTION. * Borders of ponds and wet savannas, West Indies and Costa Rica to Brazil. The type specimen from Jamaica. Costa Rica : Buenos Aires, Pittier 10589, Tonduz 3583. Cuba: Herradura, Hitchcock 155. Without locality, Wright 3871. Jamaica: Bull Head Mountain, Amer. Gr. Nat. Herb. 46. Santo Domingo: Without locality, Wright, Parry <& Brummel 624. Porto Rico: Trujillo Alto, Chase 6769. Trinidad: Cumuto Station, Hitchcock 10069. Piarco Savanna, Hitchcock 10347. AGROSTOIDIA. 48. Panicum condensum Nash. Panicum condensum Nash in Small, Fl. Southeast. U. S. 93, 1903; Contr. U. S. Nat. Herb. 15: 102. 1910. DISTRIBUTION. Swamps and borders of ponds and streams, Pennsylvania to Florida and Texas near the coast, south into Mexico and tlie West Indies. The type specimen from Florida. Veracruz: Without locality,Goitin 10. Bahamas: Nassau, Cur tins 174. Cuba: Banks of Guanabo River, Le6n 4141. Along Gibora car- retera north of Holguin, Shafcr 1438. Han&bana, Wright 184 in 1865. Without locality, Wright 3862 in part. Jamaica: Savanna-la-Mar, Hitck- cock 9884. Black River, Amer. Gr. 2Vat. Herb. 47. Porto Rico: Santurce, Chase 6351. Campo Alegre, T agnna del Tortuguero, Chase 6802. Leeward Islands: Guadeloupe, Duss 3919. LAXA. All the species are pereitnial. Spikelets not expanded at maturity by an enlarged sterile palea, pointed. Nodes glabrous; spikelets 2.5 mm. long 49. P. fongum. Nodes densely pubescent; spikelets not over 1.5 mm. long.. 50. P. polygonatum. Fig. 66,—Distribution of P. xlcnodes. Fig, (^—Distribution of P. condensum. HITCHCOCK AND CHASE—TROPICAL NORTH AMERICAN PANICT7M. 493 Spikelets expanded at maturity by the enlarged sterile palea, usually blunt. Panicle branches not racemose; blades scarcely wider than their sheaths; eterilo palea conspicuously enlarged. Spikelets 3 mm. long, congested; panicles dark purple.. 58. P. cupreum. Spikelets not over 2A mm. long; panicles green or pale. Panicle branches spikelet-bearing or branchlet bearing along the upper half or toward the ends only 57. P. kians. Panicle branches branchlet-bearing throughout their length or nearly so..... !.... 56. P, exiguiflorum. Panicle branches subracemose, the epikelets secund; blades at least 5 mm. wide; enlarged sterile palea not con- spicuous. Blades narrowed toward the base 54. P. laxwn. Blades cordate or truncate at base. Spikelets 2 mm. long; panicle branches erect or nearly so 55. P. stevenaianum. Spikelets not over 1.6 mm. long, usually less; panicle branches spreading or ascending. Panicles one-third to half as wide as long; spike- lets not conspicuously secund, somewhat irregularly disposed; blades cordate- clasping 53. P. boliviense. Panicles rarely one-fourth as wide as long; spike- lets conspicuously secund and regularly disposed. Culms as much as 2 meters long; panicles 25 to 30 cm. long 51. P. fnilhjtorum. Culms not over 1 meter long; panicles 5 to 15 cm. long : 52. P. jrilosum. 49. Panicum longum Hitchc. & Chase. Panicum longum Hitchc. & Chase, Contr. U. S, Nat. Herb. 15: 111. 1910. DISTRIBUTION. Swamps, State of Veracruz. The only collections known are from near Jalapa, Pringle 8195 (the type) and Schiede & Deppe 674 (Halle Herb.). 50. Panicum polygonatum Schxad. Panicum polygonatum Schrad. in Schult. Mant. 2: 256. 1824; Contr. U. S. Nat. Herb. 15:112. 1910. DISTRIBUTION. Swamps and moist soil, Mexico to Paraguay. The type specimen from Brazil. Veracruz: Cdrdoba, Bourgeau 1662 in part. Guatemala: SepacuitA, Collins & Goll 08, Cook 6c Griggs 530. Cubilquitz, Tiirckheim 7797, 8795. Puerto Barrios, Kellerman 5114. Honduras: San Pedro Sula, Thieme 781, 5578, 5587 in part. * 494 CONTRIBUTIONS FBOM THE NATIONAL HERBARIUM. Costa Rica: Boruca, Tonduz 4460. Puerto Limon, Hitchcock 8421. Llano Grando de Puriscal, Jimenez 881. Hacienda (ie Gu&cimo, Tonduz 27. San Josf, Pittier 1183. Echcverrfa, Piliier 212. Tabernilla, Pittier 3824, Hitchcock 8383. Gamboa, Pittier 4798, Balboa, Hitchcock 8015. Cuba: Trinidad, Wright 753. Vento, Curtiss 598, Leon 557. Romelie, Eggers 5350. Jamaica : Port Antonio, Hitchcock in 1890. Porto Rico: Cayey, SirUmu 2471, Chase (5748. Pcmiolas, Chase 6487. Rio Pie- dras, Johnston 143. Trinidad: Port of Spain, Hitchcock 9943. Cedros, Hitchcock 10146. Venezuela: Tovar, Fendler 1443. Colombia: Santa Marta, Smith 2151. PAR YIFOLIA, Perennials, usually glaucous; culms more or less decumbent; panicles small, diffuse, the epikelets small, turgid or sub globose, glabrous, the first glume more than half the length of the spikelet. Culms very slender, decumbent or creeping; blades 1 to 3 cm. long 69. P. parmfolium. Culms firm, erect or decumbent at base only; blades 3 to 8 cm. long 70. P. cyanescens, 69. Panicum parvifolium Lam. Panicum parvifolium Lam. Tabl. Encycl. 1:173.1791; Contr. U. S. Nat. Herb. 15: 134. 1910.' The blades in this species vary in shape from oblong or ovate-lanceolate to narrowly lanceolate, in surface from glabrous to densely appressed-hirsute, and in texture from thin to firm. One form, in aspect approaching P. cyanescens, has firm pubescent erect blades, as much as 5 mm. wide and 4.5 cm. long. This is represented by Broadway 2372 in part and Ililckcock 10065, both from Trinidad. Panicum brasiliense Spreng. is a pubescent form with oblong-lanceolate moderately firm blades. It does not appear possible to recognize this form as a distinct species. HITCHCOCK AND CHASE—TROPICAL NORTH AMERICAN PANICUM. 507 DISTRIBUTION. Fig. 92.—Distribution of P. parvifolium. Wet savannas and margins of ponds and streams, Costa Rica and the West Indies to Paraguay. The type specimen from tropical America. Cost a Rica : Buenos Aires, Tonduz 3631, 3659, Pittier 10594. Cuba: Los Almacigos, Wright 3458. Herradura, Baker 2078, Tracy 9060, 9079, Hitchcock 181, Brit ton, Earle & Gager 6494. Pinar del Rfo, Britton & Gager 7075. Guane, Shafer 10659. Laguna Los Indies, Shafer 10803. Porto Rico: Lake Loisa, Chase 6786. Campo Alegre, Chase 6615,6788. Aguada, Sintenis 5719. Guainabo, Chase 6630. Catano, Sintenis 5719. Mar- tin Pefia, Chase 6358. Trujillo Alto, Chase 6763. VegaBaja, Chase 6796, Heller 1316. Trinidad: Cumuto Station, Hitchcock 10065, Amer. Gr, Nat. Herb, 72. Pitch Lake, Hitchcock 10100. Arima, Broadway 2372, Without locality, Crueger, 224. 70. Panicum cyanescens Nees. Panicum, cyanescens Nees, Agrost. Bras. 220.1829, "Habitat in Brasilia meridionali (Sellow)." The type is in the Berlin Herbarium. Panicum firmifolium Trin,; Nees, loc. cit. A herbarium name giver, as a synonym of P. cyanescens. DESCRIPTION. Plants perennial, bluish or glaucous; culms tufted, erect or with a decumbent base rooting at the nodes, slender, smooth, leafy, 30 to 50 cm. high, branching from the mid- dle and upper nodes; sheaths striate, glabrous, rarely ciliate on the overlapping margin; ligule minute, membranaceous, sparsely cilia te with long hairs or sometimes naked; blades flat, rather firm, erect, spreading or refiexed, 3 to 8 cm. long, 4 to 5 mm. wide, oblong-lanceolate, slightly narrowed to the base, acute, glabrous; panicles short-exserted, terminal and often from the upper sheaths, 3 to 6 cm. long, as wide or wider, open, the slender flexuous branches rather remote, stiffly ascend- ing or spreading, naked below, branching and epikelet- bearing toward the ends, the spikelets on slender divaricate pedicels; spikelets about 1.5 mm. long, 0.9 mm. wide, tuigid or subglobose, obtuse, glabrous; first glume two-thirds to three-fourths as long as the spikelet; second glume and sterile lemma equal, covering the fruit, or at maturity the glume wrinkled because of the turgidily of the fruit, exposing the summit; fruit 1,2 mm. long, 0.8 mm. wide, very turgid, subacute, the lemma and palea cellular-roughened as seen under a lens, bearing a few very obscure appressed hairs toward the summit. This species resembles P. parvifolium, but differs in the less slender, more erect culms, longer blades, and stiffly ascending panicle branches, naked below. Fio. 93.—P. evanescent. From type specimen. 508 CONTRIBUTIONS FBOM TIIE NATIONAL HERBARIUM. Fio. 94.—Distribution of P. cyaiwscens. DISTRIBUTION. Swampa and wet savannas, British Honduras and Trinidad to Brazil. British Honduras : Manatee La- goon, Peck 271 (Gray Herb.). Trinidad: FiarcoSavanna, Hitch- cock 10349,10354,10364. Cu- mu to Station, Hitchcock 10067. Aripo Savanna, Broadway 2377. tTNGROTTPED SPECIES OF TRUE PANICUM. 71. Panicum pyrularium Bp. nov. Plants annual; culms delicate, 10 to 13 cm. high, at first erect and simple, finally decumbent and branching, often rooting at the nodes, more or less zigzag, sometimes elongating to 25 or 3p cm.; nodes sparsely pilose or glabrous; sheaths shorter than the blades, glabrous or sparsely pilose; ligule mcmbranaceous, about 0.5 mm. long; blades thin, flat, spreading, 1 to 3 cm. long, 2 to 7 mm. wide (the lower sometimes smaller), narrowly elliptical, somewhat clasping at base, obtuse or acutish at the apex, scabrous on the margins, glabrous or sparsely pilose on both surfaces, sometimes glaucous; panicles terminating the culm and branches, loose and open, 2 to 5 cm. long, about as wide, ova! or pyramidal in outline, the delicate fiexuous branches and branchlets spreading or refiexed, smooth, the capillary divaricate pedicels several times longer than the spikelets; spikelets 1.5 mm. long, 0.6 mm. wide, turgid, pyriform, long-attenuate at base, glabrous; first glume about half as long as the spikelet, acute; second glume and sterile lemma 5-nerved, not exceeding the fruit, the glume slightly shorter than the sterile lemma; fruit 1 mm. long, 0.5 mm. wide, turgid. Type in the U. S. National Herbarium, no. 715639, collected between Hato del Jobo and Cerro Vaca, eastern Chiriquf, Panama, altitude 700 to 1,000 meters, December 25 to 28, 1911, by H. Pittier (no. 5416). Panicum pyrularium, one of the smallest and most delicate species in the genus, is not related to any North American species. The South American Panicum polycomum, Trin. is an allied species of more tufted habit, with much narrower blades, smaller panicles, and smaller pubescent spikelets not attenuate at base. None of the label* with the specimens cited below indicates the habitat. DISTRIBUTION. Panama to Venezuela. Panama : Between Hato del Jobo and Cerro Vaca, Ohiriquf, Pittier 5416. Ven ezuela : Tovar, Fendler 2502. Colombia: Santa Marta, Smith 2570. Without locality, JVi- ana 281 (2811?). FiO. 93.—P. pyru- larium. From type specimen. Fig. yfi.—Distribution ol P. vyrularium. HITCHCOCK AND CHASE—TROPICAL NORTH AMERICAN PANICUM. 509 72. Panicum haenkeanum Preel. Panicum haenkeanum Presl, Rel. Haenk. 1: 304. 1830. "Hab. in Mexico." The type specimen is in the herbarium of the National Museum at Prague. The only datum on the label is the word "Mexico." Panicum costaricense Hack. Oesterr. Bot. Zeitschr. 51: 428. 1901; Contr. IT. S. Nat. Herb. 16: 134.1910. For discussion of Panicum expansum Fourn,, mentioned in the Revision under P. costaricense, see page 525 under P, cordovense. Field study of this species shows that it is a perennial with straggling culms as much as 2 meters long, often rooting at the lower nodes. DISTRIBUTION. Moist wooded or grassy banks and slopes, Mexico to Panama. Costa Rica: T&raba, Tonduz 3628, 3636, 3673. Boruca, Pittier 4626. Cordoncillal, Pittier 3640. Buenos Aires, Tonduz 3687, 4860, Pittier 3661. Panama: Culebra, Hitchcock 9168. Between Corozal and Ancon, Pittier 2169,2636. San Felix, Pittier 5247. Between Panama and Corozal, Hitchcock 9206. 73. Fig. 97.—Distribution of P. hacnkeanuTtt. ineptum Bp. no v. DESCRIPTION. Fig. 98.—P. ineptitvt. From type specimen. Plants perennial (?); culms slender, apparently ascending, probably 50 em. or more long, slender, striate-fluted, glabrous or the upper internodea sparsely pilose, producing nearly simple branches as much as 25 cm. long; nodes retrorsely pubescent; sheaths loose, shorter than the intemodes, pilose, the maxgins densely ciliate; ligule ciliate, about 0.5 mm. long; blades spreading, flat, 3 to 7 cm. long, 3 to 6 mm. wide, tapering from the truncate base to an acumi- nate apex, softly pilose on both surfaces; panicles terminal, those of the branches short-exeerted, 3 to 5 cm. long, consisting of few to several short spread- ing densely flowered branches, remote along the slender pilose axis, the branches 4 to 6 mm. long, bearing 1 to 8 subsessile spikelets, the rachis pilose; spikelets 2.5 to 2.7 mm. long, 1.1 mm. wide, blunt; first glume about half as long as the spikelet, 3-nerved, obtuse, pubescent; second glume and sterile lemma equal, inflated, much larger than the fruit, the glumegibbous in the middle, 7-nerved, pubescent, the sterile lemma 3-nerved, glabrous, inclosing a membranaceous palea; fruit 1.6 mm. long, 0.9 mm. wide, elliptical, smooth and shining, the lemma strongly convex. Type in the herbarium of Krug & Urban in the Berlin Botanical Mu- seum, the ticket reading " 817 Panicum- Fig. 99.—Distribution of P. inepttim. •S. Domingo, Bertero. Hb. Spr." A slip in Sprengel' a hand bears the name'' Panicum nemoroaum Sw.'' [Ichnanthus nemoroms]. 510 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM, The type specimen, consists of a culm with four internodes, the base and summit wanting, bearing two flowering branches. No other collection of the species is known. It appears to bo related to Panicum vene&uelae Hack., from which it differs in the smaller panicle and in the smaller and pubescent instead of bristly hispid spikelets. 74. Panicum xnillegxana Poir. Panicum millegrana Poir. in Lam. Encyd. Suppl. 4 : 278. 1816; Contr. TJ. S. Nat. Herb. 15 : 135. 1910. Panicum, patentmimum Desv.; Poir. in Lam. Encycl. Suppl. 4: 283.1816. "Cette pi ante croit & Saint-Dominique & & la Nouvelle-Espagne." The type from the her- barium of Desvaux in the Paris Herbarium is a fragmentary specimen consisting of a panicle with immature glabrous spikelets together with a few broken leaves. DISTRIBUTION. Damp woods and shady banks, Mexico and the West Indies to Paraguay. The type specimen from tropical America, probably from Cayenne. Veracruz: C6rdoba, Arner. Gr. Nat. Herb. 73. Jalapa, Hitchcock 6605, Holway 3083. Mirador, Liebmann, 275. Oaxaca: Without locality, Galeotli 5728. Chiapas: Santa Rosa, Heyde . 510. Sheaths pubescent. Spikelets 4 mm. long, pyriform 104. P. nodutum. Spikelets not over 2.6 mm. long. Spikelets attenuate at base, mostly prominently pustulose; blades narrow, stiff, strongly nerved, tapering from base to apex; autumnal form often bushy- branched See Angustifolia, p. 514, »Obs. But. 3: 9. 1783. t HITCHCOCK AND CHASE—TBOPICAL NORTH AMERICAN PANICUM. 5X3 Spikelets not attenuate at base. Culms tall, usually 75 cm. high or more; foliage velvety- pubescent See Scop aria, p, 523. Culms not over 60 cm. high Spikelets not over 1.3 mm. long; sheaths and culms appressed-pu- bescent See Spreta, p. 518. Spikelets 1.7 to 2.4 mm. long; plants conspic- uously pubescent, at least on the sheaths. See Lanuginosa, p. 519. LAXIFLORA. Spikelets papillose-pilose; sheaths retrorsely pilose 78. P. xalapense. Spikelets glabrous; sheaths not retrorsely pilose. Blades glabrous on the surface 79. P, polycaulon. Blades pilose on the surface 80. P. strigosum. 78. Panic um xalapense H. B. K. Panicum xalapense H. B. K. Nov. Gen. & Sp. 1:103.1816; Contr. U. S. Nat. Herb. 16: 159.1910. DISTRIBUTION. Moist banks and rich woods, southeastern United States to Guatemala; also Santo Domingo. The type specimen from Jal&pa. IIidalgo: Trinidad Iron Works, Pringle 13250. Puebla: Chinantla, Liebmann 328. Veracruz: Jalapa, Pringle 8083, Hitchcock 6687, Amer. Gr. Nat. Herb. 84, &mt£A 1752. C6rdoba, Bourgeau 2162. Boca del Monte, Nelson 201, Seler 2160. Guatemala : Cobdn, TUrckkeim Fig. 101—Distribution of P. xalapense. 3831. Santo Dominoo: Constanza, Tilrckheim 3059. Rio Yaqui near Jarabacoa, Eggera 2129. 79. Panicum polycaulon Nash. Panicum, dichotomum /? glabretcens Griseb. Fl. Brit. W. Ind. 553. 1864. "Pd. [Furdie], in mountain-savannahs [Jamaica]." The type specimen is in the Kew Herbarium. Pameum polycaulon Nash, Bull. Torrey Club 34:200.1897; Contr. XT. S. Nat. Herb. 16:163. 1910. 82472°—16 6 514 CONTRIBUTIONS FROM THE NATIONAL HEKBABIUM. DISTRIBUTION. Open moist woods and savannas, Florida and the Greater Antilles. The type specimen from Florida. Cuba: Sierra Nipe near Wood (red, Shafer 3083. Herradura, Hitch- cock 115. Isle of Pines, Palmer & Riley 990. Without locality, Wright 3875 in part. Jamaica: Hills back of Barican, Hitchcock 9561. Bull Head Mountain, Hitchcock 9550. Porto Rico: Aguada, Sintenti 5724. Monte Mesa, Chase 6276. Trujillo Alto, Chase 6767. Campo Alegre, Chase 6621. 80. Panicum strigosum Muhl. Panicum strigosum Muhl. in Ell. Bot. S. 0. & Ga, 1; 126. 1816; Contr, U. S. Nat. Herb. 15: 164.1910. distribution . Sandy woods and open moist ground, southeastern United States to Colombia and in the Greater Antilles. Type specimen from South Carolina or Georgia. Veracruz: Minatitl&n, Smith 555. Guatemala: Road fromGual&nto Cop&n, Pittier 1800. Secan- qufm, Pittier 257. Costa Rica: Between De Can- delaria and San Cristobal, Jimenez 459. Cuba: El Guama, Palmer & Riley 213. Without locality, Wright 3875 in part. JAMAICA: Bull Head Mountain, Hitchcock 9551. Santo Domingo: Without locality, Eggers 2045 (K. U. Herb.). Colombia: Santa Marta, Smith 163. ANGCSTIFOLIA. Nodes bearded; plants grayish-villous; autumnal blades flat, rather soft 82. P. chrysopsidi/olium. Nodes not bearded; plants villous only at base, or nearly glabrous; autumnal blades involute. Spikelets 3 to 3.5 mm. long, pointed 83. P./usi/orme. Spikelets less than 3 mm. long, not pointed or obscurely so. Plants glabrous or nearly so; autumnal culms erect. Spikelets subeecund along the euberect panicle branches 86. P. neuranthum. Spikelets not subsecund; panicle loose and open. 85. P. ovinum. Plants pubescent, at least on the lower half. Spikelets about 2.4 mm., rarely only 2.1 mm., long; vernal blades 7 to 12 cm. long; autumnal blades not falcate 84. P, arenicoloides. Spikelets not over 2 mm. long; vernal blades 4 to 6 cm. long; autumnal blades much crowded, falcate 81. P. aciculare. Fig. 105.—Distribution of P. polycaulon. HITCHCOCK AND CHASE—TROPICAL NORTH AMERICAN PANICUM. 515 81. Panicum adculare Deev. Fig. 107.—Distribution of P. ocfcufore. Panicum adculare Deev.; Poir. in Lam. Encycl, Suppl. 4: 274. 1816; Contr. U. S. Nat. Herb. 16: 166,1910. In the discussion of the type specimen it is stated that it probably came from the southeastern United States. As the species is now known to occur in Porto Rico, it becomes probable that this island is the type locality, since Deevaux described many species from there. DISTRIBUTION. Grassy slopes and sandy woods, southeastern United States, Cuba, and Porto Rico. Cuba: Pinar del Rfo, Britton 8275» 8303, 8328. FiG. 137.—Distribution of P. coriovense. Fig. 136.—P. cordovmse. From Hitchcock 8328. HITCHCOCK AND CHASE—TROPICAL NORTH AMERICAN PANICUM, 527 110. Panicum chiriquiense «p. nov. DESCRIPTION. Plants perennial, olivaceous; culms straggling, creeping and rooting at the lower nodes, softly papillose-pilose, freely branching, the leafy fertile branches ascending, 20 to 30 cm. high; nodes pilose; sheaths nearly as long as the internodes or the upper overlapping, softly papillose-pilose; ligiile about 0.5 mm. long; blades flat, somewhat spreading, 4 to 7 cm. long, 7 to 10 mm. wide, nar- rowly lanceolate, unsymmetrical at base and often somewhat falcate, acuminate, softly papillose- villous beneath, rather sparsely pilose on the upper surface; panicles shart-exsertod or included at base, 2.5 to 3.5 cm. long, half to two-thirds as wide, the few branches ascending, the axis and few nearly simple branches slender, viilous; spike- lets short-pediceled, 2.6 to 2.8 mm. long, about 1.1 mm. wide, elliptical; first glume about three- fourths as long as the spikelet, acute, 3-nerved, ^ m _p cWri?t(lejM<. viilous; second glume and sterile lemma equal, type spocinifiii. covering the fruit, the glume viilous, minutely apiculate, the lemma usually subinduratc, smooth and shining in the two middle internerves, the midnerve suppressed or evident at the summit only, the lateral mternerves viilous; fruit 2.1 mm. long, 1 mm. wide, minutely apiculate. Type in the U. S. National Herbarium, no. 725186, collected "in shade along trail, hillside jungle, foothills, vicinity of El Boquete, province of Chiriquf, Panama, altitude 1,000 to 1,300 meters, October 4, 1911," by A. S. Hitchcock (no. 8313). Known only from the type collec- tion. This speciea differs from P. cor- doiense in the viilous foliage with shorter, unsymmetrical blades, the less elongate culms, and the smaller spikelets. In the specimens collected all the panicles are terminal on the branches. Whether or not the plants at an earlier season bear large panicles on a primary culm is not known. The character of the suppressed midnerve and smooth middle internerves, rare in P. eordovense, is usual and emphasised in P. chiri- quiense. Only an occasional spikelet in panicles with the usual form has undifFer- entiated middle internerves. MISCEIiLAltEOTrS SPECIES. 111. Panicum obtuaum H. B. K. Panicum obtusuvn H. B. K. Nov. Gen. & Sp. 1; 98, 1816; Contr. U. S. Nat. Herb. 15: 321.1910. DISTRIBUTION. Moist sandy or gravelly soil, southwestern United States to central Mexico. The type specimen from Guanajuato. Sonora: Nogales to Cocoepora Ranch, Griffiths 6800. Chihuahua: Between Casaa Grand ea and Sabinal, Nelson 6352. Chihuahua, Pringle 476. Mifiaca, Hitchcock 7734. Fia. 139.—Distribution of P. ckiriquieiwe. 528 CONTRIBUTIONS FBOM THE NATIONAL HERBARIUM Durango: Durango, Palmer 175 in 1896, Hitchcock 7618. Torrefin, Hitchcock 7563. Coahuila: Saltillo, Palmer 394 and 504 in 1898, Hitchcock 5582. La Ventura, Nelson 3908. Jaral, Schumann 1714. Nuevo Le6n: Monterrey, Hitchcock 5533. Zacatecas: Concepcifin del Oro, Palmer 266 in 1904. Zacatecas, Hitchcock 7525. Aquascalientes: Aguascalientea, Rose