82 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 21 



Atlantic analogue: Paradasygyius tuberculatus (Lemos de Castro, 



1949). 



Diagnosis: Carapace depressed, finely granulate, rostrum simple. 

 Chelae of male turgid, dactyl without large basal tooth. Legs long, 

 cylindrical, hairy, first ambulatory shortest. A large conical spine on 

 male first abdominal segment. Male first pleopod thickened, tapering 

 gradually to apex, which is provided with several longer spinules, orifice 

 elongate, lip little projecting. 



Description: Carapace depressed, covered with fine granulations with 

 here and there occasional larger ones ; a short stout spine near the margin 

 of the branchial region. Epimeral plates well developed and produced 

 in a spine between the second and third, and third and fourth ambulatory 

 legs. Rostrum triangular, tipped with a small, slightly capitate spine. 

 Eyes large, flattened. Basal antennal article with dentate margins, 

 terminating in two teeth, the outer the longer, incurved at tip. Second 

 article (or first movable article) of the antennules exceeding in length 

 the fossa, and in large specimens exceeding the rostrum. Maxillipeds 

 rather widely separated ; ischium with a shallow sulcus ; merus strongly 

 cordiform, very narrow at base. 



Chelipeds of male stout, granulate; margins of merus tuberculate; 

 palm inflated, subglobular; fingers narrowly gaping at base, finely 

 crenulate in the gape, crenate along meeting edges; dactylus with a 

 notch at base. Chelipeds of female weaker than legs, palms not swollen. 

 The ambulatory legs [in the female] diminishing in the order 3, 2, 4, 1, 

 three and two being nearly the same length; granulate and hairy, the 

 first pair conspicuously hairy with a fringe of hair on either side; the 

 hairiness diminishing from the first to the fourth pair, and the granula- 

 tion diminishing from the proximal to the distal end of each leg; dactyli 

 unarmed. 



First segment of abdomen armed with a long, horizontal, conical, 

 acute spine. In the male the sides of the last two segments subparallel, 

 the extremity broadly rounded. In the mature female the last or fused 

 segment much wider than long, almost covering the sternum laterally, 

 the distal margins straight or slightly concave. Sternum of male flat, 

 except in front of the chelipeds; there, in both sexes, a smooth swelling 

 and anterior to that a small spine between the maxillipeds. (Rathbun, 

 1925, modified) 



Material examined: 104 specimens from 33 Hancock expeditions 

 stations, of which 19 were in the Gulf of California. (See Table 10) 

 From Ensenada de San Francisco, mainland side, and outside Conception 



