2 BULLETIN OF THE 



four fifths as broad as long, or with the breadth including spines about equal 

 to the length excluding the rostral horns, which are strongly divergent, nearly 

 straight, and in the adult less than half as long as the rest of the carapax. 

 The supra-orbital spines are large, acute, and much more prominent than the 

 obtuse post-orbital processes. The basal segment of the antenna is armed with 

 two large and nearly equal spines beneath the eye, one near the base, the other 

 near the tip. The hepatic region projects above the lateral margin in a promi- 

 nent spine about a third of the way from the orbit to the great branchial spine. 

 The anterior angles of the buccal area project in angular dentiform processes, 

 back of which the prominent margin of the pleural region is armed with two 

 or three small and unequal spines. There are six spines or spiniform tuber- 

 cles on the gastric region, two median, and each side two slightly smaller 

 lateral, which are nearer together than the median. There are three median 

 spiniform tubercles on the cardiac region, of which the middle one is much the 

 more prominent, and back of these the posterior margin of the cardiac region 

 projects in a prominent median spine, either side of which the postero-lateral 

 margin is ornamented with a regular series of six or seven minute tubercles. 

 The middle of the branchial region projects in a spine directed straight out- 

 ward and a little upward, which is the largest upon the carapax, and about half 

 as long as the rostral horns ; on a line between this and the postero-lateral 

 gastric spine there are two spines near together ; and back of these on the 

 posterior part of the region there is a single spine opposite the large cardiac 

 spine. In addition to these dorsal spines of the branchial region there is a 

 lateral closely set series of three or four small spines just below the pleural 

 suture and above the base of the cheliped, and a similar but isolated spine 

 below and back of the great branchial spine. The entire surface of the cara- 

 pax and of the sternum, and of the exposed parts of the appendages, except the 

 terminal portions of the chelae and of the dactyli of the ambulatory legs, is 

 covered with soft scabrous papillae, and sparsely clothed with short setce. 



The chelipeds are a little longer than the carapax including the rostral horns, 

 and scarcely stouter than the ambulatory legs ; the chela is nearly as long as 

 and no stouter than the merus, the basal portion subcylindrical, nearly naked 

 and smooth except for minute, scattered papillae, like those on the surface 

 generally except that they are smaller and much more scattered ; the digits are 

 a little more than half as "long as the basal portion, a little curved, slightly com- 

 pressed, smooth, and with the prehensile edges regularly dentate. The ambula- 

 tory legs are all armed with a dentiform spine at tlie distal end of the merus ; 

 the first pair are nearly twice as long as the chelipeds, and the succeeding pairs 

 are successively a little shorter. 



The second and third segments of the abdomen of the male are expanded, 

 and tlie first ami second are each armed with a small median tubercle. 



Station 319, N. Lat. 32° 25', W. Long. 77° 42' 30", 262 fath. ; 1 ^. 



A very much smaller specimen (Plate II. fig. 3) from Station 317 differs so 

 much from the one above described that it might readily be n)istaken for a dis- 

 tinct species. It is apparently an immature male, and diflers in having a 



