OP ARTS AND SCIENCES. 115 



acumen ; upper surface of rostrum concave, sides thickened, punctate- 

 lined. Post-orbital ridges without spines, slightly swollen at the 

 posterior end. Carapace longer than the abdomen, oval, punctate, 

 granulated on sides, posterior dorsal margin depressed, cervical groove 

 hardly sinuate, crossing the median line of the back half-way between 

 the base of the rostrum and the posterior margin of" the carapace ; lat- 

 eral and branchiostegian spines obsolete ; sub-orbital angle little de- 

 veloped, obtuse ; areola narrow, with two irregular longitudinal rows 

 of dots. Epistoma subquadrangular. Abdomen small, short ; ante- 

 rior segment of telson bispinose on each side, posterior segment 

 rounded behind. Antennje shorter than the body, second and third 

 segments without spines, scale small. External maxillipeds hairy 

 within. Chela punctate, inner margin of hand serrato-tuberculate, 

 outer margin thickened, serrate ; fingers somewhat down-curved, 

 slightly gaping, toothed on their opposed mai'gins. Carpus with a 

 strong tooth on the inner side, teeth of the lower side obsolescent. 

 Superior border of meros serrate, lower side armed with two rows of 

 spines. Third pair of legs hooked. First pair of abdominal legs of 

 the first form of the male short, thick, twisted, internal part cylindri- 

 cal, recurved, with pointed apex ; external part broader, plane within, 

 apex recurved, compressed, external margin corneous, striated. 



Length, 62 mm. Length of carapace, 33.5 mm. Length of abdo- 

 men, 28.5 mm. Length of rostrum, 5 mm. Metacarapace, 15 mm. 

 AVidth of areola, L5 mm. 



Known localities. West Virginia : Cranberry Summit, Preston Co. 

 Virginia : Pennington's Gap, Lee Co. Tennessee : Cumberland Gap. 



This species has the general appearance of G. Diogenes, but the ros- 

 trum is short, as in C. Bartonii, and the areola is not obliterated in 

 the middle by the apposition of the branchio-cardiac lines. The few 

 (four) specimens which I have seen come from the Appalachian 

 Mountain region of Virginia and West Virginia. According to 

 Mr. Uhler, it makes mud chimneys like 0. Diogenes, which it seems 

 to represent in the mountain regions, C. Diogenes belonging to the 

 lowlands. 



7. C. ARGILLICOLA, Sp. nov. 



Rostrum short, broad, down-curved, excavated, with a deep foveola 

 at base; acumen short, broadly triangular, acute, no lateral spines. 

 Post-orbital ridges without anterior spines, swollen behind. Cephalo- 

 thorax laterally compressed, carapace punctate, anterior border not 

 angulaled, cervical groove sinuate, no lateral or branchiostegian spine. 



