^'Wx'] PROCEEDINGS OF THE NATIONAL MITSEUM. 233 



is inncli more swollen than in the male; the cbelipeds are M'eaker, tlie 

 hands narrow, the fingers in contact for nearly their whole length. 



Yonng males: These resemble the females in the areolations of the 

 braiudiial regions and in the chelipeds. 



Dimensions of a male in millimeters: Entire leng'th of cara])a('e, 11; 

 width, without spines, <».5; length of cheliped, about 13; width of hand, 

 3.3. 



IJECOIM) OF SI'KCIMENS KXAMIXED. 



Sonthcrn California; W. H. Dall (17r)0(]). 



SuiiDiej^^o; ('. II. Orciitt (17371); 10 fathoms, H. iroinpliill (4283). 

 Cataliiia Island, drtMlgod .January, 18G3; ,J. (i. Coopcu- (17372). 



Lat. 3h N., long. 119 29' 30" W., 30 fatbonis, i)cbble.s, .station 2945, U. S. Fish 

 (Jonnnis.sion steamer AJhalross, 1S89 (17028). 



This species is much smaller than richii, which is found in the same 

 localities, and it is at once disting-uished from the latter by the hepatic 

 region; in ricliii it is dilated in two flattened horizontal spines, while 

 inf/rt7//itis furnished with one slender spine and a flattened obtuse 

 oval tooth not horizontal. 



Subfamily NeoriiynchinvE. 



Neorhynchus mexicanus. 



Carapace broadly triangular, convex; regions well marked; surface 

 granulate *ind tuberculate, the tubercles becoming spinous on the lat- 

 eral margins and on the summit of the branchial regions. On the 

 median line there is a spiny tubercle on the [)osterioi" part of the gastric 

 region, a. stout si)ine on the cardiac aiul on the intestinal region. There 

 is al.S(> a shorter sjune on the lirst abdominal segment pointing upward 

 and backward. Kostrnm triangular, a])ex mucronate. Postorbital 

 spines longer than the eyes, the tips pointing forward. Male abdomen 

 with first segment long, one-spiued; second, .'^hort; third, wide; next 

 three segments gradually tapering; seventh, subtriangular, anchylo.sed 

 with the sixth. Sternum conspicuously granulate, deeply grooved be- 

 tween the seginents. Female abdomen with large flattened granules, 

 live-segmented, the first segment with a si)ine; the .second, third, ami 

 fourth, short; the lifth, suborbicular, convex. Basal antennal joint 

 with its outer margin prolonged in a slender spine, slightly incurved, 

 not quite so mm^h advanced as the rostrum. Ischium of external max- 

 illil)eds, with the longitudinal groove de<'p; merus not .so deeply cor- 

 date as in d('2)res.sHS. Chelipeds of male short, rather stout, granulate; 

 merus si)inulous on lower margins; hand broad, inflated, with a tu 

 bercle on the outer surface near the carpus; fingers nearly as long as 

 the palni, gaping at the base. Chelii)eds of female more slender than 

 in the male, margins of hand parallel, fingers slightly gaping. Anibu 

 latoi'y legs long, slender, cylindrical, granulate under the lens, slightly 

 pubescent, gradually <liminishing in size from the first to the fourth; 

 dactyls with acute horny ti|ts. 



