206 
MARINE SHELLS OF WEST COAST OF NORTH AMERICA 
moderately rounded, marked by fine, closely spaced, spiral striations. 
Aperture large, oval; posterior angle acute; outer lip thin; inner lip strong, 
moderately curved, and partly reflected over the base to which it is 
appressed, provided with a strong fold at its insertion. Length, 3.4; 
diameter, 1.6 mm. (Bartsch.) 
Cotypes in Geological Survey of Canada and United States National 
Museum, No. 220116. Type locality, Skidegate, Queen Charlotte Islands, 
British Columbia. 
Range. Skidegate, Queen Charlotte Islands, British Columbia, to 
Trinidad, California. 
Odostomia spreadboroughi Dali and Bartsch, 1910 
Canada, Department of Mines, Geological Survey Branch, Memoir No. 14-N, 17; 
Pi. 2, fig. 2. 
Shell elongate-ovate, somewhat translucent, bluish-white. Nuclear 
whorls small, deeply, very obliquely immersed within the first of the suc¬ 
ceeding turns. Post-nuclear whorls flattened in the middle, rounded 
strongly at the summit and the suture, marked by decidedly sinuous, ex¬ 
ceedingly fine lines of growth and fine spiral striations; the latter are less 
strongly developed on the posterior two-thirds between the sutures than 
on the anterior third and on the base. Sutures strongly constricted. Peri¬ 
phery of the last whorl and base inflated, well-rounded, the latter deeply 
and strongly umbilicated. Aperture oval; posterior angle acute; outer 
lip thin, showing the external sculpture within; columella very slender, 
strongly curved and slightly revolute, provided with a very faint, oblique 
fold a little anterior to its insertion; parietal wall glazed with a thin callus. 
Length, 3.8; diameter, 1.9 mm. (Dali and Bartsch.) 
Type in Geological Survey Museum, Ottawa, and in United States 
National Museum, No. 211541. Type locality, ship channel, Barkley 
Sound, Vancouver Island, British Columbia. 
Range. Known only from type locality. 
Odostomia stephensae Dali and Bartsch, 1909 
Bulletin 68, United States National Museum, 210; PI. 24, fig. 5. 
Shell elongate-conic, bluish-white. Nuclear whorls almost completely 
immersed in the first of the succeeding turns, above which only the outer 
edge of the last volution projects. Post-nuclear whorls rather high between 
the sutures, moderately rounded, ornamented by numerous, fine but well- 
incised, subequal and subequally spaced, spiral lines; about thirty-three of 
which appear between the summit and the periphery of the last whorl. 
Suture well-marked. Periphery of last whorl well-rounded. Base rather 
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