404 BULLETIN 97, UNITED STATES NATIONAL MUSEUM. 



granulate. H-form depression very shallow. Front about one-third 

 the anterior width of the carapace, edge scarcely visible in dorsal 

 view, eyebrow partly visible. Upper margin of orbit very sinuous 

 and oblique. Antero-lateral angles almost rectangular. Lateral 

 margins for the most part convex, slightly sinuous posteriorly; 

 typically they slope outward a little from the orbital angle, so that 

 the carapace is widest behind that angle, but such is not always the 

 case, as one side may slope out and the other in. 



Arm of large cheliped of male granulate-rugose; wrist and hand 

 coarsely granulate, granules on the latter increasing in size above. 

 Surface of the palm strongly bent over above, a longitudinal sulcus at 

 the bend. Inner face with a tuberculated zigzag ridge across the 

 middle; a small area of fine granules on the upper half. Fingers 

 one and one-third times as long as palm; prehensile tubercles of 

 pollex coarser than these of dactylus, which has, however, several 

 large tubercles. For the rest, much as in U. pugnax. 



Measurements. Male (22319), length of carapace 13.6, width of 

 same 19.8 mm. 



Habitat. Lives on salt flats. 



Range. Galapagos Islands; Peru. 



Material examined. 



Galapagos Islands: James Island; Apr. 11, 1888; Albatross; 

 1 male (22320). Indefatigable Island; Apr. 12, 1888; Albatross,' 

 6 males (types) (22319). South Seymour Island; May 3, 1899; 

 Stanford University; 2 males, 1 female (25665). 



Puerto Grande, Rio Zarumilla (2 leagues from Capon), Peru; 

 salt flats; Feb. 2, 1908; R. E. Coker; 5 males (40488). 



UCA MACRODACTYLUS (Milne Edward* and Lucas). 



Plate 143. 



Gelasimus macrodaetylus MILNE EDWARDS and LUCAS, in d'Orbijmy's Voy. 



dans l'Am6r. Merid., vol. 6, 1843, Crust., p. 27 ; vol. 9, atlas, 1847, pi. 11, 



fig. 3 (type-locality, Cdtcs du Valparaiso; type in Paris Mus.). 

 Gelasimus anmilipes KINGSLEY, Proc. Acnd. Nat. Sci. Philadelphia, 1880, 



p. 148 (part). (Not Milne Edwards.) 

 Uca macrodactyla NOBILI, Boll. Mus. Zool. Auat. comp. R. Univ. Torino, 



vol. 16, 1902, No. 415, p. 49. 



Diagnosis. Carapace strongly narrowed behind. Oblique ridge 

 inside palm continued to upper margin. Short sulcus outside palm 

 at base of thumb. 



Description. Convexity moderate. H-fovm depression shallow; 

 sulcus behind the orbit deep. 



Front about one-third width of carapace. Orbits very oblique, 

 slightly sinuous. Sides strongly converging, sinuous; carapace 

 widest at antero-lateral angles, which are subacute. 



