CLASS GASTROPODA 
177 
Odostomia enora Dali and Bartsch, 1909 
Bulletin 68, United States National Museum, 189; PI. 21, fig. 2. 
Shell elongate-ovate, milk-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 well-rounded, 
slightly contracted at the sutures and weakly shouldered at the summits, 
marked between the sutures by four, feebly incised, spiral grooves, of 
which the second one above the periphery is the weakest. Periphery of the 
last whorl somewhat inflated. Base well-rounded, posteriorly, somewhat 
attenuated anteriorly, marked by four, subequal but unequally spaced, 
incised lines. Aperture oval, somewhat efifuse anteriorly; posterior angle 
acute; outer lip thin, columella slender, slightly curved and somewhat 
revolute, provided with a weak fold at its insertion. Length, 2.8; diameter, 
1.3 mm. (Dali and Bartsch.) 
Type in United States National Museum, No. 207126. Type locality, 
San Pedro, California. 
Range. Known only from type locality. 
Odostomia exara Dali and Bartsch, 1907 
Plate 57, fig. 6 
Proceedings of the United States National Museum, 33:521; PI. 46, fig. 6. 
Shell elongate-ovate, subdiaphanous. Nuclear whorls smooth, deeply 
immersed in the first of the succeeding turns, only a part of the last one 
appearing above it. Post-nuclear whorls somewhat inflated, well-rounded, 
marked on the first whorl by eight, on the second by twelve, on the third 
by fourteen, and on the penultimate between the sutures by twenty, sub¬ 
equal and equally spaced, low, depressed spiral cords which are separated 
by narrower channels. Periphery and base of the last whorl inflated, 
sculptured like the spire by probably twenty spiral cords. In addition to 
the spiral sculpture the entire surface is marked by fine incremental lines, 
which are best marked in the spaces between the cords. Aperture oval, 
somewhat efifuse anteriorly; posterior angle acute; outer lip thin, showing 
the external sculpture within; columella decidedly curved, re-enforced by 
the attenuated base, free only at its anterior extremity, where it is some¬ 
what revolute, provided with a prominent fold at its insertion, which 
appears as the thickened inflection of the columella; parietal wall covered 
by a thin callus. Length, 3.9; diameter, 2.1 mm. (Dali and Bartsch.) 
Type in United States National Museum, No. 196250. Type locality, 
Pacific Grove, California. 
Range. Known only from type locality. 
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