Boone, Crustacea, Cruises of ''Eagle" and "Ara," 1921-28 221 



gaping about one and one-fifth times as long as the palm — in older 

 males even longer; the upper finger is the longer, with the tip de- 

 cidedly down-curved. The small male cheliped is weak, the finger 

 spoon-shaped, for holding and sieving mud. The female chelipeds are 

 weak, subequal, similar to the small one of the male. 



The ambulatories are slender, decreasing in length in the order: 

 3, 2, 1, 4, the meral joint stout and long, the carpal and propodal 

 joints very setose, the dactyli slender, long sharp. 



Between the second and third ambulatories at the base is an aper- 

 ture into the branchial cavity, which is guarded by a heavy tuft of 

 close setae. This aperture permits the crab to control the water 

 content of the branchial cavity. 



Synonymy. — Gelasimus vocans Gould, Kept. Invert. Mass., p. 325 

 (part), 1841. 



Gelasimus vocans, variety A, DeKay, Nat. Hist. New York Crust., 

 p. 14, pi. 6, fig. 10, 1844. 



Gelasimus pugilator LeConte, Proc. Acad. Nat. Sci. Phila., vol. 7, 

 p. 403, 1855. 



Gelasimus palustris Smith, Amer. Nat., vol. 3, p. 557, 1870. 



Gelasimus pugnax Smith, Trans. Conn. Acad. Arts and Sci., vol. 2, 

 p. 131, pi. 2, fig. 1, pi. 4, figs. 2-2d, 1870. 



Gelasimus vocator Ejngsley, Proc. Acad. Nat. Sci. Phila., p. 147 

 (part), 1880. 



TJca vocator Ortmann, Zool. Jahrb. Syst., vol. 10, p. 352 (part), 1897. 



TJca pugnax Rathbun, Amer. Nat., vol. 34, p. 585, 1900 ; Bull. 97, U. S. 

 Nat. Mus., p. 395, pi. 139, 1918. 



Uca color adensis (Eathbun). 



Plate 74, figs. A and B. 



Diagnostic characters: This is a little species; the carapace has 

 the frontal border one-fourth the width of the carapace; the lateral 

 margins angled, straight anteriorly, then abruptly directed inward 

 at the widest point. The male great cheliped has the upper surface 

 of the palm at right angles to the outer face. The oblique ridge inside 

 the palm is continued to the upper margin. 



