342 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL.21 



Female abdomen seven-segmented also. 



Range: Eastern tropical Pacific: Clarion Island, Mexico, Bay of 

 Panama, and Ecuador. 48-182 fathoms. The genus contains but one 

 species. 



Maiopsis panamensis Faxon 

 Plate U, Figs. 3, 3a; Plate 38, Figs. 1, 2; Plate 39, Fig. 1 



Maiopsis panamensis Faxon, 1893, p. 151; 1895, p. 13, pi. 2. Rathbun, 

 1925, p. 338, P l. 247. 



Type: Male holotype, M.C.Z. No. 4480, length to base of rostrum 

 112 mm, rostrum 22 mm, width 113.5 mm. 



Type locality: Bay of Panama, 182 fathoms, Albatross station 3355. 



Localities subsequently reported, with collectors: Known only from 

 the type locality above. 



Atlantic analogue: None. A Panamic species. 



Diagnosis: Carapace extremely spiny, three spines at distal end of 

 meri. Two deep supraorbital fissures and an interorbital spine. Basal 

 antennal article very broad, three spines on anterior margin. Male sev- 

 enth abdominal somite broader than long, truncate terminally. Male 

 first pleopod long, slender, cylindrical, tapering toward apex, grooved 

 along concave border, and twisted so that the groove distally reaches the 

 convex border, where its ridges enclose the subterminal aperture, pro- 

 tected also proximally by a minute flap; a single row of inconspicuous 

 setae on concave margin between aperture and needle-sharp tip. 



Description: Dorsal surface of carapace thickly set with spines of 

 various sizes and scattered hooked setae. The largest spines distributed 

 as follows: five on the gastric region, one on the genital, one on the 

 cardiac, four on the intestinal, and about seven on each branchial region. 

 Margin of carapace armed with twelve prominent spines, three of them 

 on the hepatic region. [Chelipeds and] legs covered with numerous spiny 

 tubercles; the meri armed with three or more prominent spines at the 

 distal end. Chela long and slender, the tubercles of the hand smaller than 

 on the other parts of the legs ; fingers nearly smooth ; a deep pit at base 

 of movable finger. 



Sternum ornamented with small tubercles along each side of the 

 abdomen. First abdominal segment furnished with a bidentate tubercle. 

 (Faxon, 1893) 



Female with principal spines of carapace distributed as in male except 

 on intestinal region ; this region with but one prominent spine, the median 

 intestinal, instead of four. Seven spines of each branchial region arranged 



