NO. 2182. NEW SPECIES OF CRETACEOUS CRABS— RATHBUN. 387 



Front deflexed, subtriangular, broader than long, bilobed at 

 extremity, medially grooved, sides elevated, granulate. 



Orbits inclined forward and outward and, in front view, downward; 

 divided into two sockets, the inner one the larger, and with a spine on 

 its lower border. Eyes reaching very little mto the second socket 

 and tapering distally. 



One joint of the antennule is seen just below the origin of the eye 

 and has granulated edges. 



Outer maxillipeds only partially shown. Exognath half as wide as 

 endognath, of which only the ischium is visible and that has the end 

 broken off. Even so, it reaches forward beyond the line of the ros- 

 trum. There appears to be a space between the two maxillipeds. 

 Their edges are finely granulated. 



Chelipeds over twice as long as carapace. Merus massive, a little 

 compressed, widest at the middle, granules in several rows on the mar- 

 gms, scarce elsewhere. Carpus slightly longer than wide, outer or 

 upper surface granulate, with a longitudinal groove through its mid- 

 dle, inner margin spinulose. Palm nearly as high as its superior 

 length, granules arranged iiTegularly in wide lengthwise bands, and 

 more spinulose than elsewhere. Fingers elongate, two or three times 

 as long as palm, compressed, granulate about the edges. The fingers 

 themselves are not preserved, but only their impression. 



Only the proximal portions of the ambulatory legs can be made out. 

 First three pairs similar and of good size; the ischiiun and merus 

 jomts are granulate, and the latter are compressed. The last pair are 

 slender and much reduced in length and are probably subdorsal; very 

 little of them remains except the first segment. 



Most of the specimens showing the ventral surface are males, but 

 five are females. The genital ducts are to be seen at the base of the 

 fifth pereiopods in the male, of the third in the female. The sternal 

 segments are granulate through the middle ; the first segment bears 

 a transverse depression. The abdomen is composed of seven separate 

 segments in both sexes ; in the male it is oblong with the sides some- 

 what convergent, in the female it is subovate. 



Relationships. — ^This form approaches Polycnemidi^m pustulosum 

 Reuss from the Cretaceous of Bohemia,* in the areolation of the cara- 

 pace and the extent of the fronto-orbital region, but the latter has 

 the carapace more strongly convergent posteriorly and nothing is 

 known of its appendages. 



1 Denk. k. Akad. Wiss., math.-natui. CL, vol. 17, 1859, p. 6, pi. 3, fig. 1. 



