316 BULLETIN 152, UNITED STATES NATIONAL MUSEUM 



Diagnosis. — Nine lateral teeth behind orbital tooth. Carapace 

 very deeply lobulated anteriorly, lobules bordered with hair on front 

 edge. Median notch of front deep. Wrist and hand covered above 

 with large tubercles. 



Description. — Very strongly lobulated in front, each lobule bordered 

 anteriorly by some very short hairs. Antero-lateral border cut into 

 nine slightly irregular teeth, the first one separated from the orbital 

 angle by a, furrow. The two median lobes of the front terminate in 

 a straight border and are separated on the median line by a wider 

 and deeper notch than in denticulatus ; inner orbital angle dentiform. 

 Basal antenna! article short, barely reaching the subfrontal pro- 

 longation. Wrist and palm covered above with large rugose tubercles ; 

 one or two irregular granulate crests on outer face of palm. Fingers 

 strongly channeled. 



Color. — Ecru drab, movable finger drab, chela and fixed finger like 

 carapace only lighter; first, second, and third legs except dactyls 

 olive and just a fleck of olive on each side of dactyls (Schmitt). 



Measurements. — Male, length of carapace 7.8 mm. (0.31 inch), 

 width 11.2 mm. (0.44 inch) (Stimpson). 



Range. — From Mexico (mouth of Gulf of California) to Ecuador. 



Recorded localities. — Cape St. Lucas, Lower California (Stimpson 

 and A. Milne Edwards); Mazatlan, Sinaloa, Mexico (Lockington) ; 

 Baia di Sant' Elena, Ecuador (Nobili). 



Material examined. — MEXICO. — Cape St. Lucas; J. Xantus; 3 

 males, cotypes (1257, M.C.Z.). Santa Isabel Island, Tepic Terri- 

 tory; on rocks; Secretaria de Agricultura y Fomento; 1 male (61031). 



PANAMA. — Taboga Island, Bay of Panama; under stones at low 

 tide; May, 1927; Melbourne Ward; 1 male, 1 female; returned. 



ECUADOR.— 1926; W. L. Schmitt: South side Point Santa 

 Elena; September 17; 3 males, 1 female, 2 young (60834, 60970). 

 Salinas; September 12-14; 3 males, 1 female, 3 young (60833, 60835, 

 60969, 60971). 



Genus LOPHOXANTHUS A. Milne Edwards 



Lophoxanthus A. Milne Edwards, Crust. Reg. Mex., 1879, p. 256; type, L- 

 lamellipes (Stimpson). — Rathbun, Bull. Labor. Nat. Hist. State Univ. 

 Iowa, vol. 4, 1898, p. 272. 



Carapace flat, suboctagonal, slightly areolated; antero-lateral teeth 

 N, T and S subequal, D and E obsolete. Front narrow, deflexed, 

 thickened. Orbits small, subcircular, one fissure above. Chelipeds 

 massive; carpus broader than long; manus and digits veiy high; 

 lower margin of propodus nearly straight. Ambulatory legs broad, 

 cristate. Male abdominal segments 3-5 partially fused. 



Contains only one species. 



