Subfamily Fissurellinae
Genus Fissurella Bruguière 1789
Subgenus Cremides H. and A. Adams 1854
Plate 17d
Lower Florida Keys and the West Indies.
1 to 11⁄2 inches in length. 20 to 22 strongly nodulated, radial ribs. Margin sharply crenulated. Interior pure-white. Orifice oblong. An intertidal rock-dweller. Uncommon in Florida and the Bahamas; abundant in the West Indies.
Plate 17f
Southeast Florida, Bermuda and the West Indies.
1 to 11⁄2 inches in length. With irregular radiating ribs. Orifice almost round. Inside with green and whitish concentric bands. Border of orifice deep-green with a reddish-brown line. Outside grayish white to pinkish buff, generally with purplish lines between the small ribs. Commonly blotched with purple-brown. Lives on wave-dashed rocks. Common.
A similar, rather rare species, F. angusta Gmelin, also intertidal and frequently covered with calcareous algae, occurs on the Florida Keys. The shell is flattish, pointed in front, and its internal callus is light-brown to reddish brown, but not bounded by a reddish line as in barbadensis.
Plate 17e
Southeast Florida and the West Indies to Brazil.
1 inch in length, thin, flattish, narrower at the anterior end. Orifice slightly oblong. Many radiating, small, rounded riblets. Color of alternating whitish to pale-straw and pinkish rays. Interior pale-green at the margins, blending to white in the center. Green orifice callus bordered by a pinkish line. Common in beach drift. Do not confuse with the larger, more elevated F. barbadensis.
Plate 18c
Crescent City, California, to Lower California.
3⁄4 to 1 inch in length, 1⁄3 to almost 1⁄2 as high. Orifice at the very top, very slightly nearer the somewhat narrower anterior end, and elongate with deep, flat inner sides. Sculpture of numerous rather large, but low and
