68 
MARINE SHELLS OF WEST COAST OF NORTH AMERICA 
lar, smooth nucleus; suture distinct, not deep; base rounded, aperture sub- 
ovate, a distinct sharp groove in the subsutural callus, the outer lip simple, 
thick; the body with a thick coat of enamel curving into the concavely 
arcuate pillar lip; umbilicus perforate, the area bounded by a thickened, 
spirally striated ridge, parallel with the pillar lip, with the area between 
them excavated; at the anterior end of the lippar is a shallow, narrow 
sulcus, somewhat as in Trichotropis. Height of shell, 4; of last whorl, 3; 
diameter, 2.5 mm. (Dali.) 
Type in United States National Museum, No. 209891a. Type locality, 
U.S. Fish Commission Station 4322, off La Jolla, San Diego County, 
California. 
Range. Santa Rosa Island, in 53 fathoms, and off La Jolla, in 199 
fathoms. 
Genus HALOCONCHA Dali, 1886 
New name for subgenus Lacunella Deshayes, 1861. 
Shell depressed, heliciform, few-whorled, thin, with a strong epidermis; 
margin of the aperture thin, with a narrow reflexed margin in the adult, 
continuous with the thin, sharp, unreflected, arcuate columella; umbilicated 
operculum paucispiral. (Dali.) 
Example. Lacunella depressa Deshayes. 
Distribution. Alaska and Bering Sea. Fossil: Eocene, Paris basin. 
Haloconcha minor Dali, 1919 
Proceedings of the United States National Museum, 56:350. 
Shell small, purple-brownish, trochiform with about three and a half 
rounded, rapidly enlarging whorls, including a minute glassy nucleus; 
surface smooth except for incremental lines, covered with a glossy, oliva¬ 
ceous, translucent periostracum; suture distinct and deep; base rounded 
with a moderately wide umbilicus; aperture ovate, body with a layer of 
enamel connecting the two lips. Height, 5.5; longer diameter, 6; shorter 
diameter, 5 mm. (Dali.) 
Type in United States National Museum, No. 215073. Type locality, 
English Bay, St. Paul Island, Pribilof group, Bering Sea. 
Range. Commander, Pribilof, and Aleutian Islands to Chirkoff 
Island, Alaska. 
Haloconcha reflexa Dali, 1884 
Proceedings of the United States National Museum, 7:344; PI. 2, figs. 1-3. 
Shell thin; light to dark chestnut brown, smooth except for faint lines 
of growth and wrinkles of the epidermis near the suture or in the umbili- 
