No. 10 garth: brachyuran fauna of the galapagos 515 



333-35. James Bay, James Island, shore, Dec. 11, 1934, 1 male. 

 789-38. South Seymour Island, shore, Jan. 19, 1938, 4 males, 1 female. 



AIeasure?nents. — Largest specimen, male: length 35 mm, width 46 

 mm, cheliped (rigid) coxa to elbow 30 mm, elbow to tip of dactyl 30 mm, 

 chela 30 mm, dactyl 17.4 mm. 



Color in life. — General appearance light coral pink, slightly darker 

 on posterior regions and ambulatory legs. Merus of cheliped light coral 

 red, carpus coral pink, manus pinkish with yellowish crest. Eyestalks 

 bright coral red, eye pale lilac, almost white, with longitudinal dark 

 brown cornea ending in a coral pink spine. Dactyls with pale yellowish 

 tinge. (Petersen) 



Habitat. — In burrows on sandy beaches. 



Depth. — Shore. 



Re?narks. — The Ghost Crab or Cart Driver, El Carretero, as he is 

 called in Latin America, is found only on the hard-packed sand beaches 

 which occur much less frequently in the Galapagos Islands than the rocky 

 shoreline. Two striking differences separate O. gaudichaudii from the 

 species of the Mexican coast, O. occidentalis Stimpson 1860; the eyestalks 

 are prolonged beyond the cornea and the tips of the dactyls are truncate. 



Crane (1940, p. 70) presents convincing evidence that the megalops 

 described and figured by Rathbun (1924, p. 155, pi. 7) as (?) Ocypode 

 gaudichaudii and repeated by Boone (1927, p. 271, fig. 96B) with photo- 

 graphic illustration and without the question mark should be referred 

 instead to the genus Plagusia because of its grapsid, rather than ocypodid, 

 characters. 



Genus UGA Leach, 1814 

 Key to the Galapagos Species of the Genus Uca 



A^ Front less than one-third width of carapace. No granular ridge 



on superior margin of palm. Size small . . U. helleri 



A^ Front about one-third width of carapace. A granular ridge on 



superior margin of palm. Size large . . JJ. galapagensis 



Uca galapagensis Rathbun 

 Plate 87, Figs. 3, 4 



Uca galapagensis Rathbun, Proc. Washington Acad. Sci., vol. 4, p. 275, 

 pi. 12, figs. 1 and 2, 1902; Bull. 97, U.S. Nat. Mus., p. 403, pi. 142, 

 text fig. 167a and b, 1918; Zoologica, vol. 5, no. 14, p. 155, 1924. 

 Boone, Zoologica, vol. 8, no. 4, p. 271, fig. 97, upper figure, 1927; 

 not fig. 97, lower figure, which is Uca panamensis, (Stimpson). 

 Sivertsen, Med. fra det Zool. Mus., Oslo, nr. 38, p. 20, 1933. Hult, 

 Arkiv for Zoologi, Band 30A, no. 5, p. 14, 1938. 



