WEST AMERICAN PYRAMIDELLID MOLLUSKS. 55 



The type (C'at. no. 162430, U.S.N.M.) and 35 specimens were 

 dredged at U. S. Bureau of Fisheries station 2823, in 26^ fathoms, off 

 La Paz, Lower Cahfornia. The type has fourteen post-nuclear whorls 

 and measures: Ijength 5.7 mm., diameter 0.8 mm. C^at. no. 163250, 

 U.S.N.M., two from U. S. Bureau of Fisheries station 2822, 21 

 fathoms, off La Paz, Lower CaHfornia; Cat. no. 162431, U.S.N.M., 

 seven from U. S. Bureau of Fisheries stations 2826 and 2828, 9^ to 

 10 fathoms, off Cerros Island. Cat. no. 191565, U.S.N.M., three 

 specimens from U. S. Bureau of Fisheries stations 2826 and 2828, 

 off Ceralvo Island, Gulf of California, same depth and locality as the 

 preceding. 



TURBONILLA (STRIGTURBONILLA) GALAPAGENSIS, new species. 



Plate 4, fig. 7. 



Shell yellowish-white. (Early whorls decollated.) Post-nuclear 

 whorls contracted a little posterior to the middle hetween the sutureSj 

 which gives them a concave outline, slightly shouldered at the summit 

 and somewhat contracted at the sutures; marked by about 22 low, 

 rounded, almost vertical, axial ribs. Intercostal spaces almost as 

 wide as the ribs, marked by fine lines of growth, which gives them a 

 somewhat crinkly appearance, and two incised spiral lines at the 

 contracted part. Periphery and base of the last whorl well rounded, 

 marked by the continuations of the axial ribs. Aperture somewhat 

 fractured, pear-shaped ? 



The type (Cat. no. 206859, U.S.N.M.) was obtained at U. S. 

 Bureau of Fisheries station 2808, in 634 fathoms, temperature 39.9°, 

 off the Galapagos Islands. It consists of the last four and one-half 

 whorls and measures: Length 3.5 mm., diameter 1.6 mm. 



TURBONILLA (STRIGTURBONILLA) UNDATA Carpenter. 

 Plate 4, fig. 8. 

 Chemnitzia undata Carpenter, Cat. Mazatlan Shells, 1856, pp. 431, 4:^2. 



"Shell graceful, slender, soiled white. Nuclear whorls extending 

 somewhat beyond the outline of the post-nuclear spire. Post- 

 nuclear whorls subplanate, separated by strong sutures and marked 

 by about eighteen narrow, acute axial ribs which are very weak at 

 the periphery and disappear entirely on the base. Intercostal spaces 

 broad, marked by supei'ficial spiral striations which are strongest at 

 the periphery. Outer li]) thin; columella graceful, scarcely twisted." 



The above is Carpenter's description, to which he adds: "On com- 

 paring this shell with the corresponding portion of C. gracilior C. B. 

 Ads., it is found to have fewer and much finer and sharper ribs which 

 do not end at the periphery, like the curved interspaces; length 1.6 

 mm., diameter 0.55 nmi. Hab. Mazatlan; two young perfect speci- 

 mens off Spondylus; Liverpool collection, tablet 2002 contains the 

 larger specimen; the smallest is of a much darker color." 



