DESCRIPTIONS OF NEW SPECIES OF AMERICAN FRESH-WATERCRABS.
Mary J. Rathbun.(With Plates lxxiii-lxxvii.)Family PSEtTDOTHELPHUSlTLE.PSEUDOTHELPHUSA Saussure.The synonymy of this American genus with a complete list of species is given by Prof. S. I. Smith in the Transactions of the Connecti-cut Academy, Vol. n, 1870. In the Annals and Magazine ot NaturalHistory (6) in, p. 7, 1889, Mr. K. I. Pocock describes a new species (P.tenuipes) from Dominica, and gives distinguishing characteristics of allthe species. The collection of the United States National Museum con-tains no described species of Pseudothelphusa, but the genus is repre-sented by eight new species. They all possess a cervical suture, twoepigastric lobes separated by a median suture, two small Y sn?peddepressions near the posterior margin of the gastric region, and fiverows of spines on the dactyls of the ambulatory legs, three rows aboveand two below. The exognath of the external maxillipeds is shorterthan the ischium of the endognath. The species are grouped accordingto the character of the front.A'. Front not vertically deflexed, but rounding smoothly downward to the inferior 'margin.Pseudothelphusa jouyi.(PL lxxiii; PI. lxxiv, Figs. 1-3.)Carapace convex, punctate, smooth, and shining, much broader inthe male than in the female. Cervical suture short and curved, some-times not continued to the anterolateral margin. Epigastric lobesfaintly indicated by a short horizontal groove in front of them, of alighter color; sometimes the groove is obsolete, but the color remains.There is no trace of a superior frontal crest, the front rounding smoothlydown to the margin, which is not visible from above and is stronglyretreating at the center. Median sulcus shallow, dividing the frontProceedings National Museum, Vol. XVI?Xo. 959. ?49
650 NEW SPECIES OF FRESH-WATER CRABS RATHiiUN.into two lobes. Seen from in front, the margin is nearly horizontal;seen from below, the two lobes are slightly arched forward. Thereis no outer orbital fissure. The frontal and upper orbital margins areindistinctly ridged, and are granulate in small specimens; in large onesthe ridge is uneven, the normal granulation being feebly indicated.Lower orbital margin granulate. Anterolateral margins finely den-ticulate, the denticles obsolete in adult males, where the margin issimply uneven. Ischium of maxillipeds elongate, merus subtriangular,endognath but slightly overlapping the jugal area; exognath shorterthan the ischium (PL lxxiv, Fig. 3). The inferior surface of the bodyis punctate, the punctse being larger next the orbit. The cervicalsuture is present on the lower surface. The abdomen of the male(Fig. J) is widest at the distal end of the third and the proximal endof the fourth segment; lateral margins of third and fourth segmentsconvex, of fifth concave. Extremity of appendage of first segmentwith lateral expansions above, the outer one larger and with a singlesharp tooth pointing outward and downward, the inner one with aspatulate tooth pointing forward and inward (Fig. 2). The abdo-men of the female conceals the sternum. Chelipeds very unequal.Merus with short, stout spines on the inner margin; upper marginwith dentiform tubercles on the proximal two-thirds; lower outer mar-gin rounded, with a few granules; a line of granules on the inner sur-face near the carpus. Carpus punctate, with a short, broad longitu-dinal groove above and a stout inner spine. Larger hand in malemuch inflated, punctate, smooth; fingers widely gaping, with strongteeth. Smaller hand with margins subparallel, fingers almost meetingwhen closed. In the females the chelipeds are more nearly equal, andin character resemble the smaller cheliped of the male. Ambulatorylegs little compressed ; merus slender, with upper and lower marginssubparallel, upper margin blunt, with depressed spiuules, which be-come obsolete in adults; carpus feebly spinulous above; propodus,above and below.Color, a rich reddish brown.Length of $ 27"""; width, 43.5; length of large chtliped, 80. Lengthof ? 29;^ width, 40; length of large cheliped, GG.Many specimens were collected by Mr. P. L. Jouy in L892 at thefollowing localities in Mexico:Lake Chapala, about 5,000 feet elevation, among stones and shingleon lake shore; February 10, 7 $ , 80 ? , mostly with eggs (17718);Febiuary 20, 7 5,2 ? , 4 young, all small (17719).Juanacatlan, Falls of Ilio San Juan, between Lake Chapala andGuadalajara, April 2G; G 5,11 ? , mostly small (17720).Prof. A. Duges has presented specimens from Valle de Santiago,State of Guanajuato; 1 5,1 ? (17721); also an additional female(4122) from the same State, probably from the same locality.This species bears a strong resemblance to P. americana Saussurefrom Ilayti, but that species is without a cervical suture.
^ubbT1"] proceedings of the national museum. G51Pseudothelphnsa dugesi.(PI. LXXIV, Figs. 1 and 5.)This species is so closely related to jouyi that one might easily con-found the two. It can be distinguished, however, first, by the frontwhich is sinuous and slightly bilobed, more abruptly deflexed than injouyi, with a strong marginal ridge visible from above and definedby a submarginal groove; viewed from in front the margin is nearlystraight; second, by the more compressed meral joints of the ambula-tory legs, which are slightly dilated in the middle, the upper edge thin;third, by the appendages of the first segment of the male abdomen, inwhich the inner tooth at the extremity is more slender than injouyi andis directed closer to the appendage.Color, dark olive brown.Length of male 21 ; width, 33 ; length of cheliped about 53mm . Lengthof female, 20; width, 33.5; length of large cheliped, about 43.Ouemavaca, State of Morelos, Mexico, V. L. Jouy, August, 1892;7 5,1? (17722).A small female from the State of Guanajuato ( '?), A. Duges (1380),has the meral joints of the ambulatory legs proportionally wider than inthe specimens from Cuernavaca, all of which are much larger.Pseudothelphusa terrestris.(PI. LXXIV, Fi^s. 6 and 7.)This species much resembles jouyi and dugesi, but the carapace iswider, the cervical suture deeper and more conspicuous, the gastric re-gion more elevated. Front not rounding downward as in jouyi butabruptly deflexed as in dugesi, the margin strongly ridged, defined bya well-marked submarginal groove, and visible from above. Viewedfrom in front the two halves of the margin slope downward toward thecenter. The outer orbital angle is less advanced than in jouyi. Thedenticles of the anterolateral margins are less prominent than in speci-mens ofjouyi of equal size, the obliteration in adults being even morecomplete in this species. In the abdomen of the male the terminal seg-ment is more acute than injouyi; the appendage of the first segmentdiffers in having at the tip on the outer side a much narrower lateralexpansion with a narrower, sharper tooth, and on the inner side, asomewhat scythe-shaped tooth. Chelipeds similar to those of jouyi;the lower outer margin of the merus has a distinct line of granules. Theambulatory legs are more compressed, the merus joints thin above,and wide in the center.Color, olive-brown.Length of $ 21; width, 30; length of large cheliped, about 59mm.Length of 9 10; width, 32; length of large cheliped, about 33. In thisfemale specimen the chelipeds are almost equal.Collected by Mr. P. L. Jouy at Atamajac, 3 miles west of Guadalajara,April, 15, 1802,3 $ , 2 9 (17723); also at Barranca Ibarra, near Cuada-
652 NEW SPECIES OF FRESH-WATER CRABS?RATHBUN.lajara, April 20-22, L892, under stones on moist hillside, aboul L0 feetabove the river, 3,700 feel above sea level, and L,500 feei below Guada-lajara, S $ ,8 9. small (17724).A". Front vertically deflexed, forming a blunt nest.IV. t'rost smont li. Pseudothelphusa verticalis.(PI. i.wiv. Figs. 8 and it.)Carapace flattened, obscurely punctate. Cervical suture deep andshort, continued to the margin. Epigastric lobes depressed. Frontvertically detlexed; superior margin not ridged or granulate, but pre-senting a smooth, rounded surface, which is almost straighl andscarcely interrupted by the shallow median sulcus, [nfero-frontalmargin with a prominent ridge, indistinctly granulate, a submarginalgroove, and a shallow median sinus. The ridge is continuous with theorbital margin. Antero lateral margins denticulate. Orbits deeperthan [ujouyi, sometimes with a shallow hiatus. In the male abdomenthe appendages of the first segment are very different from those ofthe species above described (Fig. 9). Ohelipeds with the merus tri-angulate, broadening distally, shorter than mjouyi; upper margin withdentiform tubercles, winch become almost obsolete toward the carpus;lower inner margin with two irregular rows of spiny teeth; lower sur-face with a line of granules on the outer and distal margins; carpusshorter than mjouyi; large hand very deep and swollen, much largerthan the small hand; fingers gaping in the larger cheliped. The ambu-latory legs are compressed, broad; merus joints much dilated, with athin upper margin, obscurely denticulate.Length of S 25; width, 42; length of large cheliped 7i'""".Length of 9 22.8; width,39; length of large cheliped 54mm .Tehuantepec, Mexico. Dr. Spear; 1 3,5 9 (2537).B". Creel tuberculate. Pseudothelphusa xantusi.Carapace in shape resembling the preceding, slightly convex, punc-tate, granulate anteriorly ami laterally. There is a trace of an addi-tional suture behind the cervical suture, which is not an even curve,but turns slightly toward the horizontal near the margin. Epigastriclobes well-marked, tuberculate, separated by a deep, narrow mediansulcus, which divides the superior frontal crest. This crest is blunt,and is provided with a wide row of tubercles, and near the orbit turnsbackward, following t he line of the orbit for a short distance. Inferiorfrontal margin with a prominent ridge, which projects forward, is some-what bilobed, granulate, and Visible from above. Orbits large, nottilled by the eyes; margin granulate except for a short distance be-neath the miter angle, where the absence of granules simulates ashallow fissure. Anterolateral margin denticulate, slightly interrupted
y< uw?r''] PROCEEDINGS OP THE NATIONAL MUSEUM. 653at the cervical suture and between that suture and the orbital angle.Mcius of maxilliped more quadrate, loss triangular than in the preced-ing species. Inferior regions of the carapace very finely granulate andpunctate, cervical suture present. Jugal area pubescent as far backas the sternum. Small cheliped (the only one present) granulate,punctate, with a broad merus; inner face outlined below and distaliywith bead-like tubercles, inner margin with a double row of bluntspines, increasing in size distaliy, upper margin with spinulous rugaeextending on the outer surface distaliy. Carpus with a very shallowsulcus, a short inner spine; inner margin spinulous. Upper and lowermargins of hand subparallel ; fingers in contact. The merus joints ofthe ambulatory legs are flattened, widening toward the center, den-ticulate above; carpal and propodal joints spinulous on the upper,inner, and distal margins.Length, about 20; width, 49; length of smaller cheliped, about 01""".? Mexico, John Xantus; a single mutilated specimen, 9 (2527).This specimen is labeled 4l ('ape St. Lucas", but it is more likely tohave come from the vicinity of Manzanillo or Colima, where Mr. Xantusmade valuable collections of fresh-water fishes and mollusks in 1862.A'". Front vertically deflexed, forming an acute lamellate crest.Fseudothelphusa colombianus.(P1.LXXIV, Fig. 10; PI. LXXV, Fig. 1.)Carapace slightly convex, finely punctate, granulate anteriorly andnear the lateral margins, the granules more evident in the smallerspecimen. Epigastric lobes very prominent, the ridge continued faintlyfor a short distance in a transverse line of granules. Cervical suturecurved, becoming less marked near the lateral margin. Superiorfrontal margin lamellate, almost straight, tuberculate, divided by a V-shaped notch at the extremity of the median sulcus. The margin nearthe orbit turns nearly parallel to the orbital margin and terminates justabove the base of the eye. Interior frontal margin slightly in advanceof the superior, sinuous, with a prominent, horizontal, ridged, and granu-late margin, which is continuous with the tuberculate or crenulate or-bital margin. Front deepest at the outer ends. Anterolateral marginsdenticulate, interrupted by a shallow sinus at the cervical suture andanother between that and the orbit. External orbital fissure small andshallow, formed by the absence of one or two granules. Inferior surfaceof the carapace finely granulate near the margin. Jugal region pubes-cent and anteriorly granulate. ( 'helipeds of female unequal, punctateSmaller cheliped much like that of xantusi, but with few granules; theinner margin has a single row of spines, and below it a row of tuber-cles. Larger cheliped similar to the smaller, except that the propodus ismuch deeper (PI. lxxv, Fig. 1). Fingers in contact when closed. Am-bulatory legs little compressed; meral joints widening toward proximalend, denticulate on upper margin, and in the last pair prominently ridged
654 NEW SPECIES OF FRESH-WATER CRABS?RATHBUN.on lower outer margin ; carpal joints spinulous above and distally; pro-podal joints with small spines above, below, and distally.Length, 28.5; width, 50; length of cheliped, about 65mm .River David, Ohiriqui, United States of Colombia, about latitude 8?28' X, longitude 82? 24' VY., at an elevation of 4,000 feet above the sea;
"very rapid streams descending from Mount Ohiriqui"; J.A.McMel,July, 1883; 2 9(5512). In the same bottle there is an ambulatory legof a specimen one-half again as large, which is apparently the samespecies. Pseudothelphusa lamellifrons.
( PI.lxxv, Figs. 2-5.)The carapace of this species is allied to that of colombianus; the gran-nies of the anterior and lateral portions are, however, more prominent,and the cervical suture is supplemented by another shorter parallelsuture a little posterior to the first, but not prolonged to the margin.Front similar to that of colombiahus, but narrower and deeper. Ex-ternal orbital fissure very shallow and broad, with a denticle in themiddle. Autero-lateral margin very thin and acute, with fine teeth alittle more prominent than in colomManus and crowded close together.Ischium of maxilliped broadening noticeably at the distal end. Abdo-men of male contracted at the fifth segment (Fig. 4); the extremity ofthe appendage of the first segment is laminate, and folded and com-pressed laterally, the inner side having two lobes above, the posteriorone very large, and the outer side with a, blunt tooth pointing forwardand outward (Fig. ?">). Chelipeds in shape and armature resemblingthose of Colombian us, but the granules are prominent; the upper andlower margins of the basal portion of the larger propodus more acuratethan in those of the female of .that species. Fingers in contact. Themeral joints of the ambulatory legs are compressed, very wide at thecenter, the upper edge thin.Length, 22; width, 34.3; length of cheliped about 4(i""".Isthmus of Tehuantepee, Mexico, F. E. Sumichrast ; :> males (3289).Pseudothelphusa richmoudi.(PI. lxxv, Figs, ii-10.)Carapace more convex than in the two preceding species, finelypunctate, with scaly grannies near the lateral margin. Cervicalsnt nre deep and almost straight. Epigastric Lobes well marked.
.Median sulcus short, making a V-shaped notch in the superior frontalmargin. There are three faint depressed tubercles arranged trans-versely across the gastric region. Margins of front and orbits crenu-late or granulate. Superior frontal margin nearly straight, as seenfrom above, but seen from in front, the two sides slope downward tothe median line: the outer extremities join the orbital margin. Inferior
V( Tsi)3VI '] PROCEEDINGS OF THE NATIONAL MUSEUM. 655margin sinuous, its lobes visible from above (Fig. G). The externalorbital tooth and the next lateral tooth are finely dentate; posterior tothe cervical suture there are ten small spiniform teeth nearly equal insize, followed by a diminishing series of spinules on the posterolateralmargin; the first of the ten teeth has, on one side of the carapace, one,on the other side two, accessory spinules. Orbital fissure broad, shal-low, U-shaped. Inferior surface of the carapace granulate near thelateral margin, and granulate and pubescent on the jugal area. Max-illipeds broad, considerably overlapping the jugal area; ischium muchwider at the distal than at the proximal end ; merus more quadratethan in preceding species. Last two segments of the male abdomenlonger and narrower than in lamellifrons (Fig. 7); appendages of lirstsegment with superior portion of the extremity armed with three un-equal spines, the inferior portion having a concave oval area. (Tieli-peds unequal, punctate, with scaly granules, which form rugosities onthe outer surface of the merus; merus and carpus armed similarly tothose of colombianus, except that there is not a continuous line ofgranules near the upper margin of the inner surface. Hands rough,with scaly granules, especially on the margins. Large hand deep,lower margin very convex. Fingers in contact. Meral joints of am-bulatory legs compressed and widening toward the center; uppermargins of meral, carpal, and propodal joints, and lower margin ofpropodal joints spinulous; dactyls very slender.Length, 32.5; width without spines, 49; length of cheliped about 70mm .Found on dry land near a small creek which flows into the Escon-dido River, 50 miles from Bluefields, Nicaragua, by Mr. Charles W.Richmond, October 30, 1892; one male (17725).POTAMOCARCINTJS
.
Established by Milne Edwards* for a species (/'. armatus) whichdiffers from Pseudotkelphusa in having the superior frontal crest sharpand lamellate, and more prominent than the inferior, the carapacearmed with strong spines and an external orbital hiatus.This genus is doubtfully distinct from Ptieudothclphusa, some speciesof which have an orbital hiatus; in P. richmondi the front is sharp andlamellate, though not entirely concealing the inferior crest. In Pscu-dothelphusa can be seen every gradation between the sharp-crestedfront and the smooth front without a ridge. There seems to be no ex-ternal character to distinguish Potamocareinus except the strong mar-ginal teeth, which is hardly a generic character. The following speciesis therefore placed provisionally in this genus.
*Aim. Sci. Nat. (3), xx, p. 208, 1853.
656 NEW SPECIES OF FRESH-WATER CRABS?RATHBUN.
Potamocarcinus nicaraguensis.(PI. i.xxvi ; PI. i.xx vn, Pigs. 1 :;. |Potamocarcinus armatus Stimpsou (no 1 Milne Edwards), Proc. Acad. Nat. Sci, Phila.\. p. LOO, L858.Stimpson, iu his unpublished report od the Crustacea collected bythe North Pacific Exploring Expedition, says of P. armatus, "Wehavebill one specimen of this species, a small male, half an inch in leugth.It differs somewhal from the large female described by Milne Edwards,in thai the carapace is punctated, and. toward the lateral margins,somewhal granulated. The second and third anterolateral teeth arebifid. Dactyli scarcely quadrangular, almost rounded, also smalleraud less spinulose. It was found at Omotepec Island in Lake Nicaragua, by Mr. Charles Wright, botanisl of the expedition."Potamocarcinus nicaraguensis is a large species; small specimensagree with Stimpson's diagnosis, excepl that the dactyls are not lessspinnlons than in Milne Edwards's figure of armatus.Carapace broader anteriorly than in armatus, slightly convex, dis-tinctly marked with small punctse, granulate near the lateral margins,the granules most prominent in young specimens. Cervical sulcusdeep and curved; there are wide and deep grooves either side of theposterior gastric area, and small Y-shaped grooves between t hem. Theepigastric lobes are well marked, divided by a narrow sulcus leadingto the front. Superior frontal margin horizontal, granulate, moreadvanced in the central portion; median fissure V-shaped. Frontconcave, the inferior margin much behind the superior, the two halvesseparately arched upward. I'ostorbital tooth obtuse, outer marginrounded. Second tooth broader, obtuse, often with one or more accessoi \ teetli on its margins. Third tooth, that directly posterior to thecervical suture, broad, very variable in shape, but always bilobed.Remaining large teeth, four to six in number, irregular in shape andposition, acute, spinous. There are often small intervening teeth.Postero lateral margin with several spinules which decrease in sizefrom the lateral angle. External orbital hiatus deep and wide: orbitalmargin granulate, bower surface of the carapace granulate near thelateral margin and on thejugal area. The margin of the epistome is
I lirce spiued ; median spine long and curved upward. As in (intuitu,the endognatb of the external maxillipeds is very wide and covers aportion of the jugal region; the exognath is much shorter than iniiniidtfi, never exceeding one-half the length of the ischium. Theappendages of the first segmenl of the male abdomen are very stout,and at the summit present a concave outer surface which has a spineat the anteroinferior angle, a lobe at the antero-superior and postero-iuferior angles, and t wo spines at t he postero superior angle (PI. Lxxvij
^18?'] PROCEEDINGS OF THE NATIONAL MUSEUM. 657Fig. 3). Abdomen of female very large, concealing l he sternum. < 'helipeds long and strong, unequal, punctate; merus roughened above,inner margin spinous, the spines longer and .stronger at tlie distal end;inferior margin granulate. Carpus with a very shallow median groovenear the center, and a stout spine on the inner margin. Large handmuch swollen, deep; there is a short line of tubercles on the inner sideof the lower margin near the carpus; dactyl strongly arched ; fingersand lower surface of hand speckled with small dark spots, which, on thefingers, are granulous; teeth of prehensile edges irregular, broad, andstrong. Smaller hand less broad and deep; lingers in contact orslightly gaping; otherwise as in the larger hand. The chelipeds of thefemale are shorter and more slender than those of the male. The merusjoints of the ambulatory legs are slightly compressed; upper and lowermargins almost parallel; upper margin obscurely granulate; carpaljoints unarmed; propodal joints spinulous on the distal portion;dactyli compressed, with five rows of spines.Length of S 57mm ; width without spines, 85; approximate length oflarger cheliped, 158; length of propodus, 90; depth, 37; thickness, 23.Length of 2,63; width, without spines, 95; approximate length oflarger cheliped, 135; length of propodus, 71; depth, 25; thickness, 15.Lake Nicaragua, Dr. J. F. Bransford; 4 5,29 (5837), grading in sizefrom two inches to three-fourths of an inch in length.Near Greytown, Nicaragua, Dr. Louis F. II. Birt; 2<5,3S (13788) alllarge. Greytown is at the mouth of the river San Juan, an outlet ofLake Nicaragua.Rio Frio, Costa Rica, a tributary of the San Juan, Charles \Y. Rich-mond, March 3, 1892; one 9 (17957).EPILOBOCERA Stinipson.In 1860 Stimpson instituted the genus Epilobocera (Ann. Lye. Nat.Hist. N. Y., vii, ]>. 23-i) for a fresh-water crab of the family Thelphu-sidse, distinguished by the frontal process meeting the internal subor-bital lobe, behind which the antenna passes to the orbital cavity. Themerus of the external maxilliped is transverse, its anterior marginrounded, and the palpus goniarthroid. The type species, E. cubensis.was found in fresh-water streams near Santiago, Cuba.In 1870 Prof. S. I. Smith (Trans. ( Jonn. Acad. II, p. 150) gives a moredetailed description of E. cubensis, and describes another species, E. ar-mata, probably from the Bahamas. The generic diagnosis should beamended so as to include species in whieh the frontal process nearlyjoins tin- suborbital -lobe, the character being at best of doubtful value.The following distinguishing characters may be added: A process pro-jects from the upper side of the expiratory canal, and the exognath ofthe external maxillipeds overreaches the ischium of the endognath.I'roc. N. M. 93 42
658 NEW SPECIES OF FRESH-WATER CRABS?RATHBUN.SYNOPSIS OF SPECIES.A Superior frontal crest projecting beyond the inferior,B Carapace granulated near the margins above and below cubensis.B" Carapace nol granulated near the margins .....' a km .via.A Superior frontal crest no1 projecting beyond the inferior.IS Carapace with coarse scaly granules Dear the margins above andlie low GRANULATA.B Carapace without coarse scaly granules near Hie margins haytensis,Epilobocera haytensis.(PL lxxyii, Figs. 1 and 5.)Carapace very slightly convex, finely granulate, and punctate. Cer-vical sulcus deep. Cardiac region with shallow depressions on eitherside, and two minute Y-shaped grooves in the sulcus between thegastric and cardiac regions. Epigastric lobes distinct, separated by awell-marked sulcus, which extends forward and forms a wide mediansinus in the superior frontal margin. This margin is prominent andnearly straight when seen from above, but slopes downward toward themiddle, and in the larger specimen the two halves are inclined slightlybackward toward the median line. The margin is unevenly tubercu-late. and near the orbital border it is directed backward and ends abovethe base of the eye. The inferior margin of the front is three lobed. themedian lobe directed downward and forward, the lateral lobes roundedand horizontal, projecting well beyond the superior margin. The mar-gin is crenulate, and also the orbital border, which is continuous withit. Then; is a broad hiatus beneath the outer angle of the orbit. Theinternal suborbital lobe is very broad and concave, and nearly, but notquite, touches the subrrontal process. Tin 1 anterolateral margin ismarked by small blunt teeth, irregular in size and shape, and inter-rupted by a wide sinus at the cervical suture, and another near the ex-ternal orbital angle. The teeth become smaller and more indistinctnear the posterolateral margin, which is slightly concave, smooth, androunded The marginal teeth are less plainly marked in the smallerspecimen. Labial border of the epistonie with three lobes; median lobeacute, projecting downward and slightly forward; lateral lobes shorter,less acute, their inner margins arched upward and forward. The mar-gins of the lobes are t uberculate. On the lower side of the carapacethere is a line of tubercles following the cervical suture, and the ante-rior portion of the jugal area is tuberculate. The endognaths of the ex-ternal maxillipeds in width do not exceed the buccal cavity: the meritsis more or less quadrate, the antero-external angle rounded (Fig. 5). Themale abdomen is widest at the third segment, and does not taper regu-larly to the last, but the mar-ins of the fourth, fifth, and sixth segmentsare separately convex. The appendages of the first segment are bentoutwards at almost a righl angle near the extremities, which are lobedand spinuliferous. Chelipeds unequal. The merus is armed with stout
^lsaiy 1'] PROCEEDINGS OF THE NATIONAL MUSEUM. 659blunt spines on the inner margin, irregularly dentate on the upper mar-gin, scabrous on the upper portion of the outer surface, and with a lineof small tubercles on the lower outer margin; carpus faintly scabrousnear the merus, with a strong, blunt spine at the inner angle. Handinflated; fingers irregularly dentate within, gaping to the tips in themale, in contact in the female. Ambulatory legs flattened, sparinglypubescent; merus joints denticulate above; carpal joints indistinctlydenticulate above, with a few spinules on the distal margin; propodaljoints with two rows of spines above and below, the lower ones thelonger, and one row on the distal margin; dactyls with three rowsabove and two below, with fewer spines in the lower rows.Length of larger specimen, a female, 46nim ; width, 70. Length ofS 21.5; width, 38.Hayti; A. G. Younglese; 9 (3210). San Domingo; W. M. Gabb,1878; $ (3192). Epilobocera granulata.(PI. lxxvii, Fig. 6.)The specimens are smaller than in the preceding species, and aresexually immature. The species is closely allied to haytensis. Theareolations of the carapace are the same. The anterior portion ismore distinctly granulous, especially the epigastric lobes, and thebranchial regions are coarsely granulate near the margins. Theanterolateral margin is not interrupted at the cervical suture, butthere is a deep sinus next the postorbital tooth, and the first toothfollowing is very small. The next to 9 teeth are larger and moreregular than the remainder. Superior frontal border as in haytensis.The inferior frontal border is thin, more advanced than the superior,and in a front view the two halves are seen to arch upward. The ex-ternal suborbital fissure is very shallow, scarcely more than an inter-ruption of the denticles of the orbital border. The subhepatic andsubbranchial regions are granulate, and the cervical ridge is presentas in haytensis, but the jugal area is smooth, except at the anteriorextremity. The epistonie has three acute lobes, tuberculate on the mar-gins, similar to those of haytensis. The maxillipeds in width exceedthe buccal cavity; the merus has the antero-external angle much morearcuate than in haytensis (Fig. 0). Abdomen of male narrower than inhaytensis, especially noticeable in the penultimate segment. The merusand carpus of the chelipeds of the male are similar to those in hayten-sis; the carpal spine is sharper. Hands little dilated; fingers veryslightly gaping at their base. Ambulatory legs sparingly pubescent,with meral joints denticulate above; carpal, propodal, and terminaljoints armed as in haytensis.Length, 13.5; width, 23 millimeters.West Indies (0705). Four specimens, all more or less mutilated.Two of them are males, and probably also the other two,
660 NEW SPECIES OF FRESH-WATER CRABS? KATHBUN.
Family TRICHODACTYLID^E.Trichodactyhis quinquedentatus.(PI. lxxvii, Fig. 7.
)
Carapace very convex longitudinally, slightly convex transversely.Surface smooth, shining, punctate, the punctie irregular in size andnumerous. There is an f-|-shaped depression in (he centerof the cara-pace. Front narrower than in punctatus^ consisl iug <>l two broad lobesmore pronounced than in specimens of punctatus of equal size. Exter-nal orbital angle obtuse. Lateral margin strongly arcuate, armed withlive teeth, besides the orbital, the firsl three sharp and spinilbrin, thelast two blunt. Carapace widest at the fourth tooth. Frontal, orbitaland lateral margins ridged and smooth. Outer margin of men is ofmaxilliped ridged and more strongly produced at its anterior anglethan in punctatus. Abdomen of female covering the sternum; termi-nal segment broadly triangular, rounded at the tip. Ghelipeds infemale unequal, punctate; merns triangular, upper margin acute, witha tooth at the distal end; lower surface with a small sharp spine onthe outer and the inner margin, and a blunt projection at the extremityof the outer margin; carpus with a spine on the inner margin. Handsconvex beneath, almost straighl above; smaller hand about two thirdsas deep as larger; fingers in contact in both hands. Ambulatory legsvery slender; meral joints not dilated. Ambulatory legs, fingers, andupper portion of hand and carpus, covered with a close velvetypubescence.Length, 1!>; width, 22 millimeters.Found in a ditch, almost dry. near the Escondido River, 50 milesfrom Bluefields, Nicaragua, by Charles W. Richmond, August b"?. 1892;one female (17726).
'/'. quinquedentatus can be distinguished from other species by thenumber of lateral teeth.EXPLANATION <>K PLATES.From drawings by Mr. A. II. Baldwin.)
I'i.a 1 1: lxxiii.Pseudothelphusa jouyi, A. X 11.I'I.A I E L.XXIV.I'n.. 1. P. jouyi, five segments of male abdomen, x l:.
L'. P. jouyi, Qrsl abdominal appendage, outer side, x '?<
::. P. jouyi, external maxilliped, v - I .I. /'. dug< hi, carapace of ,( . x L$.5. P. dugeni, first abdominal appendage, outer side, ? L,6. P. terrcslris, carapace of f, x 1 .7. /'. terrestria, first abdominal appendage, outer tide, '< .8. P. vt rliriilis, largo band of I9. /'. vertivnlid, firsl abdominal appendage, upper side,10. P. colombianua, earapaco of small Yt X ' ?
vo^v ' ] PROCEEDINGS OF THE NATIONAL MUSEUM. 661Pjlate r,xxv.Fig. 1. P. colomoianus, large hand of 9, x If.
'2. I'. lamellifrons, carapace of $ , x l;.
:i. /'. lamellifrons, large hand of r? ; x l;;.I. P. lamellifrons, five segments of male abdomen, x 1;.
.".. /'. lamellifrons, first abdominal appendage, outer side, x 3$.6. P. richmondi, carapace of $, x aboul I ,,.7. P. richmondi, five segments of male abdomen, x If.8. /'. richmondi. lirst abdominal appendage, outer side, x 2jj-.!?. /'. richmondi, external maxilliped, x about 1 ,',,.10. /'. richmondi, large hand of ,' , x about 1 ', ?Plate lxxvi.Potamocarcinus nicaraguensis, <i , x J,',.Plate lxxvii.Fig. 1. /'. nicaraguensis, external maxilliped, x 1;.2. /'. nicaraguensis, five segments of male abdomen, x3. P. nicaraguensis, first abdominal appendage, outer side, x I
-1. Epilobocera haytensis, carapace of 9, x %.5. A', haytensis, externa] maxilliped, x I ;.
?i. ZJ. granulata, external maxilliped, x :!',
.
7. Trichodactylus quinquedentatus, 9, x 1;.

U. S. NATIONAL MUSEUM PROCEEDINGS, VOL. XVI PL. LXXIII

U. S. NATIONAL MUSEUM PROCEEDINGS, VOL. XVI PL. LXXIV
1-3. Pseudothelphusa jouyi.6, 7. P. terrestris.10. P. Colombia mis. 4, 5. P. dugesi.8. 9. P. verticalis.

U. S. NATIONAL MUSEUM PROCEEDINGS, VOL. XVI PL. LXXV
l. Pseudothelphusa colombiamus.0-10. p. richmondi. 2-5. P. lamellifrons.

U. S. NATIONAL MUSEUM PROCEEDINGS, VOL. XVI PL. LXXVI

U. S. NATIONAL MUSEUM PROCEEDINGS, VOL. XVI PL. LXXVII
1-3. Potamocarciniis nicaraguensis.(>. E. granulata. 4. 5. Epilnbnccra haytensis.','. Trichodactylns quinquedentatus.