526 BULLETIN 129^ UNITED STATES NATIONAL MUSEUM 



Description. — Carapace sub triangular, approximately four-sided, 

 the postero-lateral margins continuous with .the two sides of the 

 posterior margin, and the long, antero-lateral margins in line with the 

 rostral borders. Depressions separating branchial from cardiac and 

 hepatic regions deep. A narrow ridge connects cardiac and gastric 

 regions and a wider ridge the branchial and hepatic regions, below 

 which ridge there is a deep hollow, visible in side view. Prominences 

 ornamented with a few large tubercles and spines, as follows : Three 

 gastric in a triangle, the posterior the larger, one genital, two cardiac, 

 the anterior the larger, three on branchial ridge, the posterior the 

 longest. Front inclined about 45 degrees, ending in a narrow, blunt 

 tooth, and on each side above the antennules a blunt tooth, outside 

 and below which there is a small slender spine. A tubercle on each 

 preorbital lobe. A large submarginal tubercle on subhepatic region, 

 visible in dorsal view. Margin of branchial region in front of the 

 ridge cut into 9 or 10 small teeth, the second or third from the last 

 being more elongate; behind the ridge 2 or 3 small teeth. Posterior 

 margin with three distant, equal teeth. A small, blunt tooth at 

 inner lower angle of orbit; between it and angle of buccal cavity, 

 a large tubercle. A row of five tubercles near outer margin of 

 endognath. 



Chelipeds of male about two and a half times as long as carapace, 

 rather slender, especially as to merus; inner, outer and upper margins 

 of merus armed with a few, very unequal, stout spines; outer and 

 inner margins of manus armed with triangular, denticulated and very 

 unequal teeth, of which there are six or seven larger ones on inner 

 margin and three or four on outer margin; on upper surface the largest 

 tubercle is a large conical one at proximal third. Legs with merus 

 joints denticulated and dactyli furred except at tip; carpus-propodus 

 of last pair with two or three lobes above and five denticles below. 



Sternum and abdomen tuberculate, a large, transverse tubercle on 

 each abdominal segment from second to sixth inclusive. 



Variations. — Great variation in quality of spines and tubercles, 

 regardless of sex; in some specimens, the prominences are low and 

 blunt, in others high and sharp; in some, the margins of frontal lobes 

 and of orbit are denticulate, in others they are entire or subentire. 

 The amount of inclination of front is also variable. 



Color. — Uniform brick red; eggs bright red (Henderson). 



Measurements. — Male (9631), length of carapace 16.2, width of 

 same 16.8; female (15177), length of carapace 16.3, width of same 

 18.3 mm. 



Range. — Off Cape Fear, North Carolina; Gulf of Mexico along 

 coast of Florida, eastward to Miami and westward to Yucatan, 

 Mexico; Barbados. Depth, ^ to 90 fathoms. 



Material examined. — See table, page 527. 



