220 
MARINE SHELLS OF WEST COAST OF NORTH AMERICA 
marked like the spire. Aperture ovate, posterior angle obtuse; outer lip 
thin; columella short, strongly curved, reflected and provided with a 
moderately strong fold a little anterior to its insertion. Length, 7.5; 
diameter, 3.5 mm. (Dali and Bartsch.) 
Type in United States National Museum, No. 46490. Type locality, 
San Diego, California. 
Range. Santa Rosa Island to San Diego, California. 
Odostomia nuciformis Carpenter, 1865 
Plate 64, fig. 1 
Annals and Magazine of Natural History, series 3, 15:30. Bulletin 68, United States 
National Museum; PI. 28, fig. 1. 
O. testa magna, compacta, laevi, solida, alba; anfr. nucl.? . . . . 
(erosis), vertie submamillato; anfr. norm, v., subplanatis, subelongatis; 
spira brevi, marginibus valde excurvatis; basi elongata, haud umbilicata; 
apertura subovali, postice angusta; labro solido; labio tenui; plica antica, 
solida, obtusa, transversa, parietem haud attingente. Long., .3; long, spir., 
.14; lat., .18 poll. (Carpenter.) 
Shell large, shortly ovate, yellowish to milk-white. Nuclear whorls 
deeply immersed; only half of the last turn is seen in tilted position when 
viewed from above. Post-nuclear whorls increasing rapidly in size, well- 
rounded, having their summits closely appressed to the preceding whorl. 
Suture moderately well-impressed. Periphery and base of the last whorl 
well-rounded. Aperture rather large, ovate, white within; posterior angle 
acute; outer lip moderately thin at the oblique fold at its insertion; 
re-enforced by the attenuated base; parietal wall covered by a thin callus. 
Length, 7.7; diameter, 4.4 mm. (Bartsch.) 
Type in United States National Museum, No. 15517a. Type locality, 
Neah Bay, Washington. 
Range. Known only from type locality. 
Odostomia orcia Dali and Bartsch, 1909 
Bulletin 68, United States National Museum, 223; PI. 27, fig. 3. 
Shell elongate-ovate, narrowly umbilicated, yellowish-white. Nuclear 
whorls small, deeply immersed in the first of the succeeding turns, above 
which only the tilted edge of the last volution projects. Post-nuclear 
whorls well-rounded, moderately contracted at the sutures, and narrowly 
shouldered at the summit, marked by numerous, closely-spaced, wavy, 
spiral striations. Periphery and base of the last whorl inflated, well- 
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