NO. 1158. 



FRESH- WATER CRABS OF AMERICA— RATTUiVN. 



515 



marked. Lateral denticles very slightly indicated. Front very low; 

 iil)j)er boundary blunt, smootli, slightly arched forward in a dorsal view 

 and downward in a front view; lower margin strongly rimmed, sinuous 

 or trilobed (fig. '^,f). The appendages of the first segment of the abdo- 

 men of the male are laterally compressed (tig. 2, ^/, a). The cheliijeds 

 are very uneipial, and the large cheliped differs fiom those of allied 

 species in having the lingers widely gai)ing and armed with a few long 

 teeth (tig. 2, a). Ambulatory legs narrow, but not markedly slender, as 

 in (/racilipcs and e.nlipes. 



Dimensions. — Male: Length, 15.1) mm.; width, 20.5 mm.; exorbital 

 width, 8.1 mm. 



Types.— One male (No. 194K7, TT.S.N.M.), oiui female (Costa llica 

 Mus.); La Flor, a farm near Torito, Costa Kica, 1)00 to 1,000 meters 

 high; E. Fernandez, collector. 



Additional locality. — Fl Coronet, 700 

 meters; L'. BioUey and F. Fernandez, 

 one male (Costa Kica Mus.). 



PSEUDOTHELPHUSA BELLIANA, 

 new species. 



Front loin; superior margin smooth, 

 not keeled; loiver margin of larger pro- 

 podus not sinuous; sixth segment of 

 abdomen of male less than half as long 

 as its proximal width; ambulatory legs 

 elongate, the propodi at least twice as 

 long as wide. 



Carapace i)unctate, granulate neai 

 the front and antero-lateral margins. 



Lateral and posterior portions covered with short, coarse, black hairs. 

 Cervical suture rather wide, more so inwardly than outwardly, end- 

 ing a little way from the margin, slightly curved or concave forward. 

 Median suture well-marked, widening toward its posterior end. Ser- 

 rations of lateral margin small and irregular. Hei)atic and cervical 

 teeth very faintly marked, sometimes not evident. Front (fig. 3, a) 

 narrow; superior margin detlexed, smooth, save for the general granu- 

 lation of the surface, very faintly bilobed by the median sinus, the 

 margin as a whole somewhat arcuate as seen from above; seen from in 

 front it slopes downward and inward; lower margin subparallel to the 

 upper and tuberculate; intervening s))a<c concave and smooth. Orbits 

 a little wider than half the front; viewed from above, a great part of 

 the margin is nearly transverse; in a front view, the outer half is longer 

 than the innei. >Sixth and seventh segments of the male abdomen of 

 equal length (fig, 3, c). Appendages (fig, 4, b, c), similar to those 

 of jouyi. Fxognath about two-thirds length of ischium; the latter 

 widening ra[)idly distally to near the extremity, where it narrows again; 

 merus rather broad and very arcuate on the outer side (lig. 4, a). 



FlO. 2.— I'SEUDOTIIELPIIITSA AOUESTIS, 



MAi.K. a. Laroeiiciiki.a.natuualbize. 



h. MAXILLIPED, X 2J. C. AUDOMEN, NAT- 

 UKAI.SIZE. d. Left AHDOMINAL APPEND- 

 AGE, INNEIl VIEW, X 54. e. TlIK KAME, 

 LOWElt VIEW, X 5J. /. FkONT, NATURAL 

 SIZE. 



