CLASS GASTROPODA 
195 
Odostomia inflata (Carpenter) Dali and Bartsch, 1907 
Plate 63, fig. 7; Plate 66, fig. 8 
Proceedings of the United States National Museum , 33:524; PI. 47, fig. 8. 
Shell ovate, white. Nuclear whorls decollated. Post-nuclear whorls 
inflated, gently curved over the anterior two-thirds of the whorl between 
the sutures and more strongly so on the posterior third, this portion form¬ 
ing an evenly curved shoulder. Extreme summit of the whorls slightly 
flattened and narrow, rendering the sutures well-marked. Periphery of 
the last whorl subangulated. Base attenuated, rather suddenly contracted 
below the periphery, which gives the space between the periphery and the 
umbilical area a concave aspect. Entire surface marked by fine lines of 
growth and many, fine, closely placed, spiral lirations, five of which are a 
little stronger than the rest and divide the space between the sutures into 
subequal areas. There are about 30 of these threads upon the last turn 
between the summit and the periphery and about 60 on the base. Aperture 
very large, patulous anteriorly; outer lip thin at the edge but very thick 
within; columella decidedly curved, and revolute, re-enforced to the very 
edge by the attenuated base, provided with a strong oblique fold at its 
insertion. Length of the last four whorls (the others lost) 6.2; diameter, 
3.8 mm. (Dali and Bartsch.) 
Type in United States National Museum, No. 15521b. Type locality, 
Neah Bay, Washington. 
Range. Known only from type locality. 
Odostomia io Dali and Bartsch, 1903 
Memoirs of the California Academy of Sciences, 3: 281; PI. 1, fig. 14. 
Shell regularly conic, umbilicated, white. Nuclear whorls deeply 
obliquely immersed in the first of the succeeding turns, above which only 
the tilted edge of the last volution projects. Post-nuclear whorls slightly 
rounded, feebly contracted at the sutures, and very faintly shouldered 
at the summit. Sutures poorly defined. Periphery faintly angulated. 
Base somewhat inflated, well-rounded, narrowly umbilicated. Entire sur¬ 
face marked by retractive lines of growth and closely spaced spiral 
striations. Aperture ovate, somewhat effuse anteriorly; posterior angle 
acute; outer lip thin; columella slender, very strongly curved, slightly 
revolute, provided with a strong fold at its insertion. Length, 5.6; 
diameter, 2.3 mm. (Dali and Bartsch.) 
Type in United States National Museum, No. 56770. Type locality, 
Santa Rosa Island, California. 
Range. Santa Rosa Island, Catalina Island, and San Pedro, California. 
[493 ] 
