S. J. /Smith on American Crustacea. 155 



The chelipeds are short and very unequal ; in both, the merus is 

 short, not extending beyond the margin of the carapax, and trique- 

 tral, with the angles denticulate, and the carpus is small and its outer 

 surface granulous and sliglitly margined on the inner edge. In the 

 larger hand, the propodus is short and very stout, the outer surface is 

 convex and finely granulous, and the digital portion is very short, and 

 its prehensile edge directed obliquely downward; the dactylus is 

 straight, rather slender, and granulous like the propodus ; both fin- 

 gers are obtusely tubercular on the prehensile edges and have horny, 

 slightly excavated tips. The smaller hand is slender, somewhat cylin- 

 drical, the basal portion is granulous externally, and the fingers are 

 very slender, with the prehensile edges minutely toothed and the tips 

 as in the larger hand. 



The ambulatory legs are nearly naked ; the meral segments are flat 

 and each is armed with a small spine on the anterior edge near the 

 distal extremity ; the carpi are slightly bicarinated along the anterior 

 edges ; the propodi are broad, somewhat expanded in the middle, the 

 anterior edges carinated like the carpi, and the posterior edges spinu- 

 lous. The dactyli are slender, slightly curved, somewhat flattened, 

 and the angles armed with sharp spinules. 



The abdomen is broadest at the base, from which it tapers to the 

 last segment, which is longer than broad and rectangular, except that 

 the extremity is slightly rounded. 



Length of carapax, including lobes of frontal margin, 1 2 -4"^™ ; 

 breadth of carapax, including lateral teeth, IS'O"'™; ratio, 1:1*21. 

 Breadth between antero-lateral angles, 1 1 -5""". Length of ambula- 

 tory legs, first, 19™™ ; second, 25 ; third, 25 ; fourth, 21. 



I have seen only a single specimen, which was collected at Acajutla, 

 west coast of Central America, by F. H. Bradley. 



The appendages of the first abdominal segment in the male are 

 widely separated at their bases, which are articulated to a slender 

 plate arching round the intestinal canal, and converge toward their 

 tips, but do not meet, although they extend to the middle of the sixth 

 segment. Each of the organs is nearly straight and rather stout for 

 two-thirds its length, and the terminal portion is suddenly constricted 

 on the under side and curved outward and strongly downward to the 

 tip. The appendages of the second segment are small and are lodged 

 in grooves at the bases of the first pair. 



