NO. 2138. THREE SPECIES OF CRABS {OSACIIILA)—RATTIBTJN. 649 



OSACHILA TUBEROSA Stimpson. 



Plate 3G, fig. 3. 



Osachila tuhcrosa Stimpson, Bull. Mus. Comp. Zool., vol. 2, 1S71, p. 154. — 

 A. Milne Edwards, Bull. Mus. Comp. Zool., vol. 8, ISSO, p. 20 (part; 

 specimen from Sombi-ero, 54 fathoms, only). — Smith, Ann. Kept. 

 Commr. of Fish and Fisheries for 1885 (ISSG), p. G3G [32].— Rathbun, 

 Bull. Lab. Nat. Hist. State Univ. Iowa, vol. 4, 3 SOS, p. 290 (part; speci- 

 men from Station 24). 



Distinguished by its tliin-edged postero-lateral margin armed with 

 triangular teeth, the first one, which is situated at tlie Literal angle 

 of the carapace, projecting sideways beyond the antero-lateral mar- 

 gin ; the fourth or last tooth prominent, larger than the two preceding. 



Carapace not eroded all over. 



Cardiac region rounded behind. 



Upper margin of palm tridentate, the pioximal tooth l)ifid. 



Color. — Sand color with reddish cast, white below, claws and legs 

 Avhite (Henderson). 



Y aviations. — Stimpson says of tiiberosa that the lateral tooth of the 

 carapace " forms part of the branchial protuberance," This is true 

 in only two of the nine specimens examined, a female collected by 

 Stimpson (No. 2994, M. C. Z.), and a larger female bearing eggs, 

 from off Sand Key, Florida (Xo. 47955, U.S.N.M.) ; the remainder 

 of the specimens have the branchial protuberance separated b}^ more 

 or less of a furrow from the lateral tooth. The separation is most 

 evident in the largest specimen, a female (Xo. 874G, U.S.X.M). In 

 most of the G smaller specimens the depressions of the carapace are 

 wholly punctate, not eroded. In the single male (Xo. 4G044, 

 U.S.N.M.) the protuberances of the carapace are smaller and the 

 depressions deeper than in the female, the proximal tooth on the 

 upper margin of the manus is so deeply bifid that there appear to be 

 4 subequal teeth in all. (Stimpson says, "four teeth".) Stimpson 

 also says, " The cardiac protuberance is rounded and .smaller than the 

 metagastric ones." This is not true of any specimens that I have 

 seen; the cardiac protuberance may be lower but it is quite as large 

 as, or larger than, the metagastric protuberances. 



LOCALITIES OF SPECIMENS EXAJIINED BY THE WRITER. 



Off Cape Hatteras, North Carolina, lat. 35° 12' 30" N.; long. 

 75° 05' 00" W., 48 fathoms, bottom temp. 77°, crs. gy. bk. S.; Station 

 22G9, U. S. Fish Comm. Str. Alhatross, 1884; 1 female. Cat. No. 874G, 

 U.S.N.M. 



Off Sand Key, Floi-ida, 40 fathoms; J. B. Henderson collector; 1 

 male, Cat. No. 46044, U.S.N.M. 



S. by E. from Sand Key Light, Florida, Gl fathoms ; J. B. Hender- 

 son collector; 1 female ovig.. Cat. No. 47955, U.S.N.M. 



