JS. I, Smith on American Crustacea. 101 



Male. The carapax is very convex longitudinally, but scarcely at 

 all transversely. The dorsal surface is thickly beset with small, tuber- 

 culiform granules, but the space between the granules is smooth and 

 shining. The areolation is similar to that of -R spinicarpus j the cer- 

 vical suture is indicated by a very distinct, smooth sulcus, which is 

 sharp and deep in the longitudinal portions in the middle of the cara- 

 pax ; the mesogastric and the metagastric lobes are united ; there 

 are no distinct sulci between the protogastric lobes and the hepatic 

 regions ; tlie branchial regions are undivided and only indistinctly 

 separated from the cardiac. The front is lamellar, very strongly de- 

 flexed and its edge divided into two prominent, rounded lobes, which, 

 when seen in a front view, project below the inferior margins of the 

 orbits. The antero-lateral margin is thin and is divided by deep 

 rounded sinuses into four slightly upturned lobes or teeth, of which 

 the anterior, the hepatic, and the epibranchial are broad and truncate 

 and their truncated edges finely denticulated, while the posterior, or 

 mesobranchial, is acutely pointed. The inferior lateral regions are 

 grauulous like the dorsal sui-face, and, along the lateral borders, are 

 clothed with long cilia which project beyond the margins. There are 

 also, some hairs along the lateral margins of the dorsal surface, but 

 they are very easily removed. 



The outer surface of the external maxillipeds is minutely granulous. 



The chelipeds are stout and slightly unequal. The merus is trique- 

 tral and armed with a spine on the posterior angle near the distal ex- 

 tremity. The upper side of the carpus is flat, somewhat roughened, 

 and armed on the middle of the inner side with a long spine. The 

 hands are stout, slightly compressed laterally, and perfectly smooth ; 

 the upper edge is angular, but not crested, and the fingers are com- 

 pressed, deflexed, somewhat incurved, coarsely and irregularly toothed 

 within, and do not gape. 



The ambulatory legs are slender and thickly hairy along the edges, 

 especially on the dactyli, which are long, very slender, and cylindrical. 



The sternum is granulous like the carapax, only more minutely. 

 The abdomen is smooth ; the first and third segments are very much 

 wider than the second, and the penultimate is much broader than lono- 

 and its lateral margins are deeply concave in outline. The appenda- 

 ges of the first segment are long, slender, triquetral, and nearly 

 straight organs reaching almost to the extremity of the abdomen. 

 The appendages of the second segment are short and inconspicuous. 



I have seen only males. 



Trans. Connecticut Acau., Vol. II. ii April 1870 



