CLASS GASTROPODA 
223 
marked by almost vertical lines of growth and numerous, closely spaced, 
wavy, microscopic, spiral striations. Suture well-marked. Periphery of 
the last whorl well-rounded. Base rather short, inflated, narrowly umbili- 
cated and marked like the spire. Aperture broadly ovate, somewhat effuse 
anteriorly. Posterior angle acute; outer lip thin, strongly curved in the 
middle; columella slender, strongly curved and reflected anteriorly, pro¬ 
vided with a weak fold near its insertion; parietal wall glazed by a thin 
callus. Length, 5.6; diameter, 2.8 mm. (Dali and Bartsch.) 
Type in United States National Museum, No. 168809. Type locality, 
west of Amaknak Island, Unalaska. 
Range. Captain's Bay, Unalaska. 
Odostomia subglobosa Bartsch, 1912 
Proceedings of the United States National Museum, 42:286; PI. 37, fig. 2. 
Shell moderately large, subglobose, milk-white, very narrowly umbili- 
cated. Nuclear whorls small, deeply, obliquely immersed in the first of 
the succeeding turns. Post-nuclear whorls well-rounded, narrowly, tabu- 
lately shouldered at the summit; surface somewhat rough, marked by 
weak lines of growth and spiral striations; periphery of the last whorl 
strongly inflated; base short, inflated, marked like the spire. Aperture 
large, pear-shaped; posterior angle obtuse; outer lip thin at the edge, 
thick within; inner lip short, strong, twisted, and somewhat revolute, 
provided with a strong fold a little anterior to its insertion; parietal wall 
glazed with a moderately thick callus. Length, 6; diameter, 4.1 mm. 
(Bartsch.) 
Type in United States National Museum, No. 211560. Type locality, 
San Diego, California. 
Range. Known only from type locality. 
Odostomia subturrita Dali and Bartsch, 1909 
Plate 64, fig. 4 
Bulletin 68, United States National Museum, 228; PI. 28, fig. 4. 
Shell ovate, light-yellow. Nuclear whorls small, deeply obliquely im¬ 
mersed on the first of the succeeding turns, above which only the tilted 
edge of the last volution projects. Post-nuclear whorls flattened, scarcely 
at all contracted at the sutures, with a very broad tabulate summit, crossed 
by numerous spiral striations, which are a little darker-colored than the 
general surface of the shell. Periphery and base of the last whorl some¬ 
what inflated, well-rounded, marked like the spire between the sutures. 
[5211 
