download pdf

116 American Seash ells
Calliostoma variegatum Carpenter Variable Top-shell
Alaska to southern California.
Figure 33b
I inch in length, similar to doliarium, but with smaller cords which are
strongly beaded; nucleus pink; the sides of the spire slightly concave, and
the periphery of the last whorl rounded. Uncommonly dredged in 15 to
400 fathoms.
Calliostoma gloriosmn Dall Glorious Top-shell
San Francisco to San Diego, California.
Figure 33a
I inch in length, not quite so wide, rather light, with about i o fine, spiral
threads between sutures. The upper 5 are inclined to be minutely beaded.
Periphery of last whorl moderately sharp. Columella white, fairly thick and
with a swelling at the lower %. Nuclear whorls white. Color of shell yellow-
ish brown with darker purplish brown, slanting and rather elongate spots
arranged in 2 spiral series. Moderately common in shallow water.
Calliostoma splendens Carpenter Splendid Top-shell
Monterey to Lower California.
Figure 33c
/4 to H inch in length, equally wide, with about 5 to 6 whorls which
bear between sutures 5 strong spiral cords. The upper 2 or 3 arc finely
beaded, the lower 2 or 3 are smooth and cord-like. Between the cords, the
shell is brilliant orange-iridescent. General color a yellowish orange with
large white maculations on the upper half of the whorls. Moderately common
offshore, uncommonly washed ashore.
Calliosto777a ligatum Gould Ribbed Top-shell
Alaska to San Diego, California.
Figure 33g
% to I inch in length, equally wide, rather heavy; whorls quite well
rounded; characterized by smooth, spiral, light-tan cords (6 to 8 on the spire
whorls) on a background of chocolate. Sometimes flushed with mauve. No
umbilicus. Aperture usually pearly-white. A very common littoral species
from northern California north. Formerly C. costatuin Martyn.
Subfamily GIBBULINAE
Genus Livona Gray 1847
There is only one species this genus, namely L. pica from the West