54 Bulletin Vanderdilt Marine Museum, Vol. V 



inner orbital tooth. The superior orbital margin is wide, not espe- 

 cially elevated and cut by two closed sinuses on its outer half ; there 

 is a third closed sinus on the inferior margin below the outer tooth. 

 The postorbital tooth is rather broad, blunt, rendered bifid by an ob- 

 scure but constant incision. The rounded anterolateral border is cut 

 into five acute, procurved teeth, besides the bifid postorbital tooth. 

 These teeth decrease slightly in breadth and correspondingly increase 

 slightly in acuteness, the fifth or last tooth of the series being only a 

 trifle longer and sharper than the others. The postlateral margins are 

 about as long as the anterolateral but are somewhat excavate and dis- 

 tinctly convergent; the posterior margin is definitely carinate, this 

 carina continuing as a curve above the base of the natatory legs. The 

 outer portion of the sidewalls of the carapace is finely tomentose, like 

 the dorsal surface farther down towards the bases of the legs it is 

 smooth with microscopic punctae. The sternal plastron is wide, 

 smooth. The male belt is triangular, the first segment nearly con- 

 cealed; the second and third articles short and wide, transversely 

 carinated, hinge-like; the fourth and fifth articles are fused, with 

 faint suture lines visible and with an incomplete transverse median 

 ridge on the fourth segment; the sixth segment is somewhat longer 

 than the fifth, with sharply convergent sides; the seventh segment is 

 a small triangle with its proximal border curved and its tips rounded. 

 The female belt is ovate, seven-segmented, with the second and third 

 articles bluntly carinated. 



The chelipeds are two to two and one-half times the length of the 

 carapace, with the merus extending half or more than half its length 

 beyond the carapace ; three-sided, with the anterior lateral margin 

 armed with three acute, outward directed spines, which increase 

 slightly in si^e from proximal to distal. The carpus has a strong, 

 acute, spinelike tooth at the inner distal angle ; there is a small tooth 

 at its outer distal angle and above this a still smaller tooth on the 

 upper outer margin, with a brief carina running back. Behind and 

 slightly above this is a second carina terminating anteriorly in a small 

 tooth some distance back from the frontal margin of the carpus and 

 with the carina running back along the outer border of the carapace. 

 The palm is moderately high, ornamented with five costae as follows: 

 one along the lower outer margin which continues clear to the tip of 

 the lower finger ; a second costa running midway the outer surface of 

 the palm and terminating at a point between the bases of the fingers ; 

 the third costa marks the upper outer margin of the palm, and bears 



