Page:American Seashells (1954).djvu/229

Rh Trivia 7tix Schilder White Globe Trivia

Southeast Florida and the West Indies.

% inch in length, globular, pure-white in color. Characterized by about 2 2 to 26 riblets. Back with a strong groove interrupting the riblets. Alias T. nivea Gray. This is the largest and most globular of the white species found in the Western Atlantic. It is moderately uncommon.

Trivia ritteri Raymond Ritter's Trivia

Monterey, California, to Lower California.

% inch in length, globular, pure-white in color. Characterized by about 15 fine riblets that run over the bottom, sides and back of the shell without being interrupted by a dorsal groove. Uncommonly dredged on gravel bot- tom from 25 to 60 fathoms.

Trivia califorfiiana Gray Californian Trivia Plate 20V

California to Lower California.

Vs to just less than K' inch in length, rotund, and characterized by its mauve color, white, slightly depressed crease on the midline of the back, and by the fairly coarse riblets crossing over the entire shell (outer lip with about 15). A common littoral species, often washed ashore with seaweed. Also lives as deep as 40 fathoms. Trivia sangninea Sowerby, a more south- erly species, is larger, deeper purple, without the prominent white streak on the back and with finer, more numerous riblets (outer lip with about 20).

Trivia soIa?idri Sowerby Solander's Trivia Plate 20U

Catalina Island to Panama.

% to % inch in length, rotund, and characterized by the strong, raised, smooth riblets running over the lip and up onto the back. Dorsal groove deep, cream-colored and flanked by 8 to 10 cream nodules on each side. Ground color of shell dark purplish brown. Moderately common in the lit- toral zone.

Trivia radiajzs Lamarck (Lower California to Ecuador) is larger, flatter, and with a brownish spot on the back which discolors the central groove. It is fairly common.