Abt. 11 NEW AMERICAN MARINE MOLLUSKS BARTSCH 7 



tions of the axial ribs, which evanesce shortly after passing the 

 periphery, and numerous, closely spaced spiral striations. Aperture 

 large, subquadrate, posterior angle obtuse; outer lip thin showing 

 the external sculpture and color markings within; columella some- 

 what twisted, almost vertical, slightly reflected and appressed to the 

 base for the posterior third of its length ; parietal wall covered with 

 a thin callus. 



The type. Cat. No. 362146, U.S.N.M., comes from Shuyak Strait, 

 Afognak Island, Alaska. It has nine postnuclear whorls and 

 measures, length, 8.3 mm.; diameter, 2.2 mm. This species is a 

 member of the Turbonilla {Pyrgolatnpros) halia Dall and Bartsch 

 group. It differs from the other known members by its coloration 

 and flattened whorls, as well as by its size. 



TURBONILLA (PYRGOLAMPROS) ILFA, new species 



Plate 1, fig. 1 



Shell very large. Nuclear whorls decollated. The eight and a 

 quarter turns remaining narrowly shouldered at the summit, slightly 

 rounded in the middle, somewhat contracted toward the base, marked 

 by strong, well-rounded axial ribs, which are closely spaced on the 

 early whorls, rather distantly on the middle whorls, and again closely 

 placed on the last turn, where they become somewhat enfeebled. Of 

 these ribs, which are almost vertical, 22 occur upon the first of the 

 remaining turns, 24 upon the second to sixth, 26 upon the seventh and 

 30 upon the last. The spaces between the ribs are strongly impressed 

 and almost as wide as the ribs on the first two turns. On the next 

 four they are decidedly wider than the ribs, while on the next to the 

 last they again equal the ribs and on the last they are narrower. 

 The entire surface of the spire is marked, in addition, by fine spiral 

 striations. Periphery of the last whorl well rounded. Base moder- 

 ately long, well rounded, marked by the feeble continuations of the 

 axial ribs and the fine microscopic spiral striations. Aperture oval ; 

 posterior angle acute; outer lip thin; inner lip somewhat sinuous, 

 reflected over, but not appressed to the base ; parietal wall covered by 

 a thick callus. 



The type. Cat. No. 340819, U.S.N.M., was collected by A. G. Smith 

 at San Pedro, Calif. It has eight and a quarter whorls and mea- 

 sures, length, 12.5 mm. ; diameter, 4 mm. This is the largest of the 

 known West American Pyrgolampros. 



TURBONILLA (PYRGOLAMPROS) SHUYAKENSIS. new species 



Plate 2, fig. 1 



Shell broadly conic, stout, flesh colored, with a broad band of 

 chestnut brown encircling the periphery. This band extends almost 



