->. 1. Smith on American Crustacea. 139 



The abdomen is very broad, its breadth being fully equal to two- 

 thirds its length, while, in G. pugilator and allied species, the breadth 

 is not equal to more than half the length. The terminal segment is 

 very small, being rather less than half as broad as the penultimate 

 and very much shorter than broad. The appendages of the first seg- 

 ment are very stout and nearly straight organs, reaching to the middle 

 of the penultimate segment, and the tips are horny and slightly hairy, 

 while in G. pugilator these organs are longer, very slender, and 

 strongly curved outward at the tips. 



The female difi^ers from the male in having the posterior margin of 

 the carapax only slightly immarginate in the middle. 



The above description and measurements were made from three of 

 the original specimens, collected at Matamoras on the Rio Grande, 

 by M. Berlandier, and loaned by Dr. Stimpson. 



Gelasimus Stenodacylus Edwards et Lucas. 



Voyage de d'Orbigny dans I'Araerique meridionale, Crust., p. 26, p. 11, fig. 2, 1843 ; 

 Edwards, Annales des Sciences naturelles, 3me serie, Zool., tome xviii, 1852, p. 149. 



" Trouve sur les cotes du Valparaiso par M. d'Orbigny," (Edwards 

 and Lucas). In the Annales des Sciences naturelles, Edwards gives 

 the habitat as, " Chili, Bresil," but there is very likely some mistake 

 in regard to the latter locality for very few, if any, species of Crusta- 

 cea are common to Chili and Brazil. 



Gelasimns Panamensis stimpson. 



Annals Lyceum Nat. Hist, New York, vol. vii, p. 63, 1859. 

 Plate IV, figure 5. 



Stimpson had only the young of this species and did not give the 

 characters of the larger cheliped of the male, but a good series of 

 specimens collected at Panama by Mr. Bradley, shows that it is very 

 difierent from any of the east coast species and is not allied to any 

 from the west coast, unless it be to G. stenodcatylus which I have 

 not seen. 



Male. The carapax is broadest between the antero-lateral angles 

 and is much less convex than usual. The dorsal surface is very 

 minutely granulose, and there are a few coarse granules or small 

 tubercles on the front and on the anterior part of the branchial region 



