124 JS. J. Smith on American Crustacea. 



unarmed. The inferior margin of the orbit is armed with fifteen to 

 eighteen slender, compressed and truncated teeth. The jugal regions 

 are swollen and smooth, but their surfaces are veined somewhat as the 

 regions above. 



The ocular peduncles are unequal in length, the one on the side of 

 the larger cheliped being the longer, are very slender, but considera- 

 bly enlarged at the corina, and shorter than the broad and open orbits 

 which they only partially fill. 



The larger cheliped is enormously developed, the hand being high 

 and lamellar, and exceeding, in length, twice the length of the cara})ax. 

 The ischium is armed above and below with a small, marginal tuber- 

 cle. The merus is smooth and rounded posteriorly, the anterior sur- 

 face is flat and smooth, the inferior angle is armed with scatt^^red tu- 

 bercles, and the superior angle rises into a low crest toward the distal 

 portion, and is armed with slender tubercles. The carpus is smooth 

 and rounded, but is armed with one or two small tubercles at the prox- 

 imal extremity of the inner margin, and there are several low tuber- 

 cles on the outer surface. The basal portion of the propodus is short; 

 the inner surface is smooth and ixnarmed, except with a jjrominent tu- 

 bercle near the middle, from which a line of obscure tubercles extends 

 along the slight, oblique ridge to the inferior margin ; the outer sur- 

 face is covered with very large, depressed, smooth tubercles which are 

 separated by considerable spaces; and the inferior margin is thin and 

 armed Avith dentiform tubercles. The digital portion of the propodus 

 is thin and very broad toward the base ; the inner surface is smooth 

 and somewhat concave ; the outer surface is flat and very coarsely 

 punctate ; the inferior edge is denticvilate and slightly margined on 

 the outside ; and the prehensile edge is straight, except a slight exca- 

 vation at the base, is armed witli very small marginal tubercles and a 

 high, tubercular, median ridge, and at the extremity, with a slender 

 tooth. The dactylus is broadest toward the extremity ; the inner sur- 

 face is concave and smooth ; the outer surface is flat and nearly 

 smooth ; the superior edge is arcuate, thin and slightly denticulate ; 

 the prehensile edge is straight, closes closely against the propodal fin- 

 ger, except the slightly excavated portion at the base, and is armed 

 with three lines of tubercles, like the propodal finger, except that the 

 inner, mai-ginal line is separated from the median line by quite a wide 

 space toward the tip, and that one of the tul)ercles, about two-fifths 

 of the way from the base to the tip, is much larger than the rest ; and 

 the tip is armed Avith a tooth projecting perpendicularly downward. 



In the smaller cheliped, the merus is slender and its anterior edge is 



