394 BULLETIN 97, UNITED STATES NATIONAL MUSEUM. 



Diagnosis. — Oblique ridge inside hand continued toward upper 

 margin. Front very broad and shallow. Merus joints of legs not 

 enlarged. 



Description. — Carapace convex, minutely punctate and granulate, 

 branchial regions more or less plainly marked with small tubercles 

 near the outer edge; -shaped impression deep, a faint longitudinal 

 groove on branchial regions; groove behind orbital margins. Front 

 broad, about one-third width of carapace, little produced. Lower 

 edge of eyebrow with a strong convexity midway between the front 

 and lateral angles. These last are almost right angles and slightly 

 or not at all produced forward. Lateral margins of carapace for a 

 short distance nearly parallel, arching slightly outward, and then 

 converging quite strongly to the posterior margin. 



Merus of large cheliped of male marked outside with transverse, 

 sparingly setose striae; carpus long, roughened with small blunt tu- 

 bercles; hand large and stout, nearly twice as long as width of cara- 

 pace, upper surface with small tubercles which gradually become 

 smaller further down on the outer surface; lower side of the palm 

 marked with a fine raised line which fades out on the base of the 

 pollex. Inner surface of palm marked with a short, very prominent, 

 tuberculated ridge which runs from near the lower margin toward 

 the supero-proximal portion of the hand; from the upper end of 

 this ridge there is a short tuberculated ridge extending toward the 

 base of the dactyl; the prominent lower margin of the carpal groove 

 extends backward from the angle where these ridges meet, in the 

 same direction as the upper ridge; the meeting point of the 3 ridges 

 forms the apex of a large, high, three-sided pyramid. Pollex gently 

 curved, prehensile edge with a few teeth on distal half, tip truncate; 

 dactyl curving from near the middle, overreaching the pollex and 

 bearing a few prehensile teeth. Ambulatory legs slender and hairy. 

 (Abridged from Holmes.) 



Color, — Carapace in alcohol dark olivaceous (Holmes). 



Measurementf!. — Male (43352), length of carapace 19.5, width of 

 same 28.G mm. 



Habitat. — Very abundant in the woods 2 kilometers from the sea- 

 shore (Tristan). Found also in fresh water and at Todos Santos in 

 a lagoon. 



Range. — Ix)wer California to Panama. 



Material examined. — 



Cape St. Lucas, Lower California; John Xantus; 1 female 

 (M.C. Z.). 



Acapulco, Mexico; Ilassler Exped.; 3 males (M. C. Z,). 



Boca del Jesus Maria, Costa Rica: Apr. 22, 1905; P. Biolley and 

 J. F. Tristan; 1 male (32323). J. F. Tristan; 1 male, 1 female 

 (32324). 



