122 Bulletin Vanderhilt Marine Museum, Vol. V 



which latter extends backward, onto the gastric region; the frontal 

 margin is bluntly rounded at the distal angles, and separated by a 

 sulcus from the blunt superior inner orbital angle. There are two 

 closed sinuses on the outer half of the upper orbital margin, and one 

 on the outer half of the lower orbital margin, these causing three 

 lobular convolutions in the orbital margin. The inferior inner orbital 

 angle is blunt, and is in contact with the deflected margin of the 

 superior orbital angle, excluding the tip of the antennal peduncle from 

 the orbital sinus. 



The dorsal surface of the carapace is moderately convex, with the 

 regions well defined, the entire gastric region circumscribed and dis- 

 tinctly lobulated anteriorly; the anterolateral margins are rather 

 widely rounded, and are cut into four distinct teeth, in addition to the 

 postorbital angle ; the first and second teeth are bluntly lobulated, the 

 third and fourth are sharper and distinctly forward-curved. The 

 hepatic and branchial regions have three lobules, corresponding to 

 the curves of the anterolateral margin. 



The eye is set on a short bulbous, calcareous stalk, which is con- 

 stricted just below the cornea, which is terminal, hemispherical, shin- 

 ing black. 



The antennae have a large, obliquely placed peduncular article, ex- 

 cluded from the orbital sinus, and a slender multiarticulate whip. 



The external maxillipeds are close fitting, with external surface 

 finely granulose, the inner ischial margin fringed with brushlike setae. 



The male belt is narrow, five- jointed, the third, fourth and fifth 

 articles being fused. 



The right and left chelipeds are about equal in both sexes. Those 

 of the large males are about two and one-half times as long as the 

 related carapace, while in the females the chelipeds are about one and 

 three-fourths as long as the carapace. Both chelipeds have the carpus 

 smooth, convex on the upper and outer surfaces, with a prominent 

 nodular tooth at the inner angle, the propodus is smooth and high, the 

 fijigers blackish, this color extending backward behind the lower 

 finger, as a short irregular patch, on both inner and outer surfaces of 

 the palm. The fingers in the male have an elongate oval gape, meeting 

 only at the spoon-shaped tips. There are three or four very rudi- 

 mentary teeth on the lower finger and two or three denticles on the 

 upper finger. 



The ambulatories have the meral, carpal and propodal joints 

 fringed with setae along both upper and lower lateral margins, the 



