o-. g CRUSTACEA. 



The breadth of the front and narrower fingers, readily distinguish 



this species from the nitidus. 



*• 

 G. anmdipes, Edwards, Crust., ii. 55. 



Gelasimus vocans (Degeer), Desrnarest. 

 Rio Janeiro. 



Length of carapax of a male, nine and two-thirds lines ; greatest 

 breadth, fifteen lines; ratio, 1 : 1*55; length of hand, two inches and 

 five lines. The greatest breadth of the carapax is posterior to the 

 line of the anterior angles ; for the sides, instead of being straight 

 convergent from the anterior angles, are somewhat arcuate, they 

 being first divergent and then longitudinal before converging behind. 

 The front is broad subtriangular and rounded below. 



Cancer vocans, Degeer, Mem. pour servir, etc., vii. pi. 20, f. 12. 

 Gelasimus vocans, Desmarest, Crust,, p. 123; Edwards, Crust., ii. 54, and Cur. 

 Regne An., pi. 18, f. 1. 



Gelasimus maracoani, Latreille. 

 Rio Janeiro. 



Length of carapax of a male, eleven and a half lines; breadth, 

 seventeen lines ; ratio, 1 : 1*48; length of hand, two inches and two 

 lines. The anterior part of the lateral margin is longitudinal, and 

 the breadth in the line of the anterior angles is hardly less than that 

 a short distance posteriorly. From the posterior part of this longi- 

 tudinal portion a line of granules commences, which extends backward 

 near the sides of the carapax, with an inward curve. The upper 

 surface of the fourth joint of the eight posterior legs is short tomen- 

 tose, and so also, in part, that of the next joint. The basal portion of 

 the hand is small pustulous, while the lower finger is dark punctate. 

 The anterior margin is nearly straight transverse. 



In another male specimen from Rio Janeiro, closely like the pre- 

 ceding in the characters of the carapax, the front, the eight posterior 

 legs, and the maxillipeds, the large hand is not more than half as 



