THE CANCROID CRABS OF AMERICA 541 



Diagnosis. — Of large size. Carapace less than one and a half times 

 as wide as long; last two lateral teeth, though small, distinct and 

 projecting. CheUpeds smooth. 



Description. — Carapace narrow, less than one and a half times as 

 wide as long. Surface covered with depressed granules, antero- 

 lateral regions rugose. Grooves deep about the anterior portion of 

 the gastric and mesogastric regions; a broad median groove between 

 mesogastric region and edge of front. An oblique furrow runs across 

 the front and behind the orbit; from it a short branch partially sub- 

 divides the protogastric regions. There is an oblique branchial 

 ridge ending at the base of the penult lateral tooth. Front divided 

 into four well separated lobes, those of the outer pair smaller than 

 those of the inner. Orbits heavily rimmed, the rim enveloping the 

 outer suborbital tooth; a tooth below at inner angle. Behind the 

 orbital rim, 5 antero-lateral projections, the first three lobate, the 

 last two shallow teeth. 



Inner angle of carpus of cheliped blunt. Manus swollen, punctate, 

 the punctae arranged chiefly in longitudinal lines. Fingers narrow, 

 those of major chela widely gaping, teeth of movable finger larger 

 and fewer than those of the dactylus, the large basal tooth excepted. 

 Fingers of minor chela scarcely gaping, teeth numerous, those of the 

 immovable finger running larger. The color of the major fixed finger 

 runs backward and upward a little on the palm. Dactylus, propodus 

 and distal end of carpus of ambulatory legs densely pubescent. 



Color. — Slate gray with bandings of coral at meral and carpal 

 joints of ambulatory legs. (Boone.) 



Measurements. — Female (48779), length of carapace 52.4, width 

 of same 81.7, fronto-orbital width 32.7, width of front 18.1 mm. 



Range. — From Magdalena Bay, Lower California, to Ecuador 

 (Nobih). 



Material examined. — 



MEXICO.— Magdalena Bay; June, 1917; C. R. Orcutt; 1 large 

 female (Mus. San Diego Soc. Nat. Hist.). 



La Paz, Gulf of California; L. Belding; 1 female (4627). 



Teacapan, Sinaloa; from oyster beds; Secretaria de Agricultura y 

 Fomento; 1 male (61029). 



PANAMA. — Pacific shore of Panama; low tide, rocks; May-July, 

 1924; E. Deichmann; 1 male (60791). 



Taboga Island: May 12-15, 1911; Meek and Hildebrand, Smith- 

 sonian Biological Survey; 1 female (43994). June, 1914; J. Zetek; 

 2 females (48775, 48779). 



Taboguilla Island; between tide marks; October 31, 1904; Albatross; 

 1 female (33303). 



Naios Island; G. M. Gray; 1 female (42145). 



