rounded, radial ribs of varying sizes. Base of shell slightly crenulate and with color blotches. Exterior grayish white to dark-slate with numerous radial rays of mauve-pink. Interior glossy-white, often with a fine pink line around the callus at the apex. Foot of animal yellow; mantle with red stripes. Very common on rocky rubble at low tide. The variety crucifera Dall is merely a color form with white radial bands.
Subgenus Clypidella Swainson 1840
Plate 17g
Southeast Florida and the West Indies.
3⁄4 to 11⁄2 inches in length. Both ends turned up (can be rocked back and forth on a flat table). Orifice toward the anterior end, keyhole in shape. Color a faded magenta. Interior whitish, tinged with pale-green or pink. Inner callus of orifice white with a narrow red line. Uncommon in Florida.
Superfamily Patellacea
Family Acmaeidae
Subfamily Acmaeinae
Genus Lottia Sowerby 1833
Plate 18j
Crescent City, California, to Lower California.
3 to 4 inches in maximum diameter, oval in outline, low, with the apex close to the front end. Exterior dirty-brown, rough, commonly stained with algal green. Interior glossy, with a wide, dark-brown border. Center bluish with an “owl-shaped” whitish to brownish scar in the very center. Very common at or above high tide line where the sea spray may reach them. In the south they grow to a large size. Frequently polished and used as souvenirs.
Genus Acmaea Eschscholtz 1830
Subgenus Acmaea s. str.
Plate 18r
Alaska to Lower California in cold water.
1 inch in maximum diameter, thick, pure white, conic in shape, and with an almost round base. Apex pointed and near the center. Often covered with small, knobby nullipore growths. Commonly washed ashore. It lives in cold water below the low tide level.
