32 A REVISION OF THE ASTACIDJS. 



one third as long as the anterior part of the carapace). Areola broad. Ster- 

 num covered with a dense growth of coarse setae. Abdomen longer than the 

 cephalothorax. Proximal segment of telson armed on each side with four 

 spines. Anterior process of epistoma broad triangular with ciliated margin. 

 Basal segment of antennule with a sharp spine below, near the inner margin 

 of the middle of its length. Antennae shorter than the body. .Second and 

 third segments with acute external spine; scale a little longer than peduncle 

 of antenna? and rostrum, moderately broad, broadest below the middle. 

 Third maxillipeds hairy within and below. Chela moderately broad, cov- 

 ered with inconspicuous ciliate squamous tubercles, internal margin nearly 

 straight. Fingers as long as the hand, densely ciliated. Carpus tubercu- 

 late, a prominent spine within, and one near each point of articulation with 

 the chela. Meros smooth outside and inside, tuberculate and spinous above. 

 biserially spinous and ciliate beneath. Third and fourth pairs of legs toothed 

 on the third segment. Fifth pair of legs with a hook on the basal segment. 

 Anterior abdominal appendages of moderate length, articulated at the base, 

 internal part with an articulated spine obliquely placed, external part termi- 

 nating in a rounded head with two short, blunt teeth. 



Female. — Differs from the male in its shorter and smaller claws. The 

 sternum is densely ciliated, as in the male. The annulus ventralis conical 

 witli sigmoid longitudinal fissure ; movable. 



Length, 54 mm. Carapace, 26 mm. Abdomen, 29 mm. Distance from 

 tip of rostrum to cervical groove, 19 mm. ; from cervical groove to poste- 

 rior border of carapace, 7 mm. Width of areola, 3 mm. Length of chela, 

 15.5 mm. ; breadth. 4 mm. (In the female, which is 59 mm. long, the chela 

 is 12 mm. long by 4 mm. wide.) 



Two specimens, one male of the second form and one female, in the 

 F. S. National Museum (No. 3181), collected by A. Graves in McBean 

 Creek, a tributary of the Savannah River a little south of Augusta, Georgia, 

 are the types of this species. There are two young female specimens from 

 the same region, Richmond Co., in the Museum of Comparative Zoology. 



Differs from C. Lecontei and C. angustcdus by its broader areola, subplane 

 rostrum, and the pubescence of rostrum and cervical groove. The male 

 appendages also differ, as shown in the description and figures. 



