498 BULLETIN" 129^ UNITED STATES NATIONAL MUSEUM 



carapace. Antennal spines about half the length of rostral spines; 

 the margin of the antennal segment behind the spine curves outward, 

 forming a shallow lobe; preocular spines acute, half the length of 

 antennal spines. 



The arm has a dentate, laminate superior crest; wrist tuberculate; 

 palm less than twice as long as broad; fingers widely gaping, the poUex 

 being strongly curved downward. 



Legs sparsely hairy and with a few spines and tubercles; propodal 

 joints with a prominent rounded distal laminiform process for articu- 

 lation of dactylus. 



Color. — Reddish-brown above, hands and under parts white 

 marbled with bright red, the latter predominating on the upper sur- 

 face of the chelipeds (Lockington) . 



Measurements. — Male (20292), entire length of carapace 17.2, 

 width of same without spines 13.2, with spines 13.7, length of rostral 

 spines 2.5' mm. 



Range. — Lower California to Panama. 



Material examined. — 



Patos Island, Gulf of California, Mexico; anchorage, 43^ fathoms; 

 Apr. 23, 1921; Fred Baker, collector, California Academy Expedition ; 

 1 male (Cal. Acad.). 



La Paz Bay, Lower California, Mexico; L. Diguet, collector; 9 

 specimens (Paris Mus.); 1 male, 1 female (20292). 



Mazatlan, Mexico; A. Agassiz; 1 small male (2096, M. C. Z.). 



Taboga Island, Panama; June, 1894; J. Zetek; 1 male (48791). 



Island at end of breakw^ater, Panama Bay, Panama; February 5, 

 1912; Meek and Ilildebrand, Smithson. Biol. Sui*v.; 1 male (56539). 



MICROPHRYS ANTILLENSIS Rathbun 



Plate 176, figs. 3 and 4 



Microphnjs platysoma Rathbun, Bull. U. S. Fish Comm., vol. 20, for 1900, 

 pt. 2 (1901), p. 72 (part: specimens from Porto Rico). — Hay and Shore, 

 Bull. Bur. Fisheries, vol. 35, 1915-16 (1918), p. 459, pi. 38, fig. 9. 



Microphrys antillensis Rathbun, Proc. Wash. Acad. Sci., vol. 33, 1920, p. 24 

 (type-locality, off Montego .Bay Point, Jamaica; holotype, Cat. No. 

 43017, U. S. Nat. Mus.). 



Diagnosis. — Two processes on antero-lateral wall of carapace, 

 the oblong branchial process not rimmed nor sharply defined. 

 Three branchial spines about lateral angle. No lobe on margin of 

 basal antennal segment behind antero-external spine. Four equally 

 large tubercles on intestinal region. 



Description. — I formerly assigned some small Porto Rican specimens 

 to the species platysoma, but additional material indicates that the 

 Atlantic form should be separated from the Pacific. 



In M. antillensis the general aspect is the same as in platysoma. 

 The antennal spines are longer, slenderer and less divergent; the 



