WEST AMERICAN PYRAMIDELLID MOLLUSKS. 63 



region, appearino; less ])rominent on the base. About 16 of these ribs 

 occur upon the second, IS upon the fifth, and 24 upon the ])enultimate 

 post-nuclear whorl. Entire surface of the shell crossed by very 

 minute, close spiral striation. Suture subchanneled and wavy. 

 Aperture ovate, outer lip thin, joining the twisted and revolute colu- 

 mella in a broad curve. 



The type (Cat. no. 32273, U.S.N.M.) was collected at Monterey, 

 California. It has seven post-nuclear whorls and measures: Length 

 5.6 mm., diameter 2.1 mm. 



Another specimen, not quite adult (Cat. no. 176624, U.S.N.M.), 

 comes from Pacific Grove, California. This has the nuclear whorls 

 preserved, which are two, depressed heUcoid, smooth, obHquely about 

 one-fourth immersed in the first of the succeeding turns, having 

 their axis at right angles to that of the later whorls. The left side of 

 its nucleus projects slightly beyond the outline of the spire. 



The present form is in every way much more robust than T. (P.) 

 gihhosa Carpenter, which was described from ^lazatlan, Mexico, 



TURBONILLA (PYRGOLAMPROS) NEWCOMBEI Dall and Bartsch. 



Plate 6, fis- 3. 



Turhonilla (Pyrgolampros) neivcombti Dall and I5art.sch, Prnr. U. S. Nat. Mus., 

 vol. 33, 1907, p. 503, pi. 45, fig. G. 



Shell regularly, broadly conic, white on the posterior half and light 

 brown on the anterior half of the exposed portion of the whorl; base 

 white. Nuclear whorls decollated in all the specimens seen. Post- 

 nuclear whorls somewhat overhanging, decidedly contracted toward 

 the periphery from the anterior fifth of the exposed part; almost 

 flattened posterior to this, and closely appressed at the summit, sepa- 

 rated by strongly marked sutures. Ribs about 18 upon all the turns, 

 almost vertical, moderately elevated, rounded in the middle, decidedly 

 flattened and widened at the summit, disappearing at the periphery. 

 Intercostal spaces not depressed below the general surface, a little 

 wider than the ribs. Periphery and the moderately long base well 

 rounded, smooth, excepting the fine spiral striation which covers the 

 entire surface of the shell. Aperture subquadrate, posterior angle 

 acute; outer lip thin, showing the color bands within; columella 

 slender, oblique, and slightly revolute. 



The type (Cat, no, 126660, U.S.N.M,) was collected by Dr. C. F. 

 Newcombe, at Victoria, Vancouver Island, British Columbia. It has 

 seven post-nuclear whorls which measure: Length 5.4 mm., diameter 

 2.1 mm. Eighteen additional specimens were collected by Rev. 

 G, W, Taylor at Port Simpson, British Columbia, 12 of which are in 

 his collection, the other 6 form Cat. no. 196214, U.S.N.M. 



