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LITTORINIDAE 131
Shell smooth except for microscopic, spiral scratches. Color light-tan to
brown with the spire tinted with purplish rose. Often confused with Litiopa
which has a blade-like ridge on the columella just inside the aperture. Common
from low water to 25 fathoms. Alias L. divaricata Fab. and solidula
Loven.
Lacuna unifasciata Carpenter One-banded Lacuna
Monterey, California, to Lower California.
Figure 36b
^ inch in length, moderately fragile, similar to the other Lacunas, but
characterized by its very narrow, long, chink-like umbilicus and by the
carinate periphery of the whorl which bears a fine, dark-brown spiral line.
Early whorls usually pinkish, remainder yellowish tan. Umbilicus and colu-
mella white. The peripheral carina may be weak or obsolete, and the color
line may consist of a series of faint, slanting streaks of light reddish brown.
Very common in littoral seaweed and kelp in southern California.
Lacuna carinata Gould Carinate Lacuna
Alaska to Monterey, California.
Figure 36a
% to ^ inch in length, 3 to 4 whorls, moderately fragile. Aperture
semi-lunar, large. Outer lip thin. Columellar chink large, long and white.
Shell smooth, chalky-white, but always covered by a thin, yellowish brown,
smooth periostracum. Common on kelp weed. L. porrecta Cpr. and striata
Gabb are the same. Do not confuse with vincta which has a higher spire and
much narrower, brownish-tan umbilical chink.
Lacuna variegata Carpenter Variegated Lacuna
Puget Sound, Washington, to Santa Monica, California.
M inch in length, similar to unifasciata, but having a very deep umbilical
chink which is bordered by a sharp ridge. The spiral carina at the level of
the suture is very small, but quite sharp. The yellowish tan shell has mot-
tlings or oblique bands of darker color. Moderately common in eel-grass
along the shore.
Fcrmily LITTORINIDAE
Genus Haloconcha Dall 1886
Haloconcha reftexa Dall Reflexed Haloconch
Alaska and the Bering Sea.
% inch in length, fragile, 3 whorls; body whorl large. Resembles a Vel-