CAMBARUS. 79 



very prominent, ending in a spinule. Areola long and wide, 2:)lane, punc- 

 tate, in length more than one half the distance between the tip of rostrum 

 and posterior margin of the carapace ; sides nearly parallel to within a 

 short distance of the posterior margin, where they diverge. Telson bispi- 

 nous on each side. Anterior process of epistoma broad. Antenna^ longer 

 than the body, scale moderately broad, ending in long, acute apical spine. 

 Third pair of maxillipeds hairy within. Chelipeds moderate ; chela large, 

 densely punctate, inner margin short, lightly serrate ; fingers long, with 

 parallel rows of puncta, toothed within, outer one bearded within at base. 

 Carpus broad, obliquely truncated, punctate above, with a strong median 

 spine on the inner side and a small double one at the base ; below, the 

 carpus is armed with a spine on the anterior border. Meros smooth, with 

 a single ante-apical spine on the upper edge ; of the usual biserial spines 

 beneath, only two or three at the proximal end are developed. Thoracic 

 sterna naked. Third pair of legs hooked on the third segment. Fourth 

 pair of legs with a small ovate basal tubercle. First pair of abdominal 

 appendages articulated near the proximal end, stout, short, swollen in the 

 middle ; external part with the couipressed apex in the form of a strong, 

 obtuse, recurved tooth, double within ; internal part recurved, cylindrical, 

 short, acute. 



Female. — Annulus ventralis transverse, with a sigmoid sulcus. 



Measurements of an individual. — Length of body, 60 mm. ; cephalo- 

 thorax, 31 mm. ; abdomen, 29 mm. From tip of rostrum to cervical groove, 

 20 mm. ; from cervical groove to hind margin of carapace, 11 mm. Width of 

 areola, 3.5 mm. Length of rostrum, 7.5 nun. ; acumen of rostrum, 2.5 nun. ; 

 chela, 20 mm. ; inner margin of hand, 7 mm. ; fingers, 13 mm. ; antenna!, 

 58 mm. 



This species is near C. cxtrannis, but differs in its longer and narrower 

 areola, in the short hand and long fingers, the single superior ante-apical 

 spine on the meros, naked thoracic sterna (in C. cxtraiicus they are setif- 

 erous), the greater smoothness of the body altogether, and the fineness of 

 the punctation of the carapace ; the suborbital angle is very much more 

 projecting than in C. cxtraiicus. 



This species was discovered by Mr. C. L. Ilerrick in Cj'press Creek, Lau- 

 derdale Co., Ala., when collecting under the auspices of the U. S. National 

 Museum, in October, 1SS2. The specimens obtained were two males, form 

 II., and three females. 



