872 BULLETIN 97, UNITED STATES NATIONAL MUSEUM. 



OCTPODE OCCIDBNTALIS Stlmpsok. 



Plate 129, figs. 2 and 3. 



Ocypoda occidentaUs Stimpson, Ann. Lye. Ni>t. Hist. New York, vol. 7, 



1860, p. 229 (type-locality, Cape St. Lucas; cotypes, Cat. No. 201C. 



U.S.N.M. ; cotypes also in M. C. Z. and, probably, in Brit. Mus.). 

 Ocypoda gaudichaudii f Lockington, not Milne Edwards and I>ucas, Proc. 



California Acad. Sci., vol. 7, 1876 (1877), p. 145. 

 Ocypoda knhlii, var. occidentaUs Miers. Ann. Mag. Nat. Hist., ser. 5, vol. 10, 



1882, p. 386. 

 f Ocypoda urvillci Doflein, Sitzungsber. k. bayer. Akad. Wiss., math.-phys. 



CI., vol. 29, 1899, p. 189. Mollendo. Peru ; pro!>ably not O. urviUei Milne 



Edwai'ds.' 



Diagnosis. — Outer angle of orbit about as advanced as the front. 

 Eyes without style. Fingers pointed. 



Description. — Closely allied to O. albicans.^ from which it is dis- 

 tinguished by the following characters: 



The carapace is narroAver, the greatest breadth being only a sixth 

 more than its greatest length. 



Granulation of carapace more uniform and coarser. 



Outer angles of orbit more produced, being nearly or quite ns ad- 

 vanced as the front. 



Arm and wrist rougher; teeth on lower margin of propodus more 

 numerous but less prominent. Stridulating ridge longer, its tubercles 

 from 17 to 20. 



Ambulatory legs shorter, second pair not two and one-half times as 

 long as carapace, fourth pair reaching to middle of propodus of third 

 pair. Merus of all the legs as well as carpus and propodus of last pair 

 naked. Hair of carpus and propodus of first three pairs short and 

 furry, and lacking on the lower margins. Margins of merus joints 

 denticulate. 



Color. — Darkish, and can be distinguished very well on the dry 

 sand, but its color is rather confused with the sand when wet. 



Measurements. — Length of carapace of male cotype 43.2, width of 

 same 50.5 mm. 



Habits. — When pursued they run to and fro till they find them- 

 selves on soft sand, when they hide themselves quickly, diving a 

 little into the sand and confounding themselves with it to such an 

 extent that it is difficult to distinguish them. (Tristan, in letter.) 



Range. — From Turtle Bay, west coast Lower California, to Peru. 



Material examined. — 



Turtle Bay, Lower California; July 30, 1896; A. AV. Anthony; 

 4: males, 4 females (19511). 



1 Doflein had but a young specimen, and the young of occidentaUs resembles that of 

 ceratophthalma=urvlllei. 



