Page:American Seashells (1954).djvu/350

Genus Polystira Woodring 1928 Poly stir a albida Perry White Giant Turret Plate 13I South Florida, the Gulf of Mexico and the West Indies. 3 to 4 inches in length, pure-white in color. P. virgo Lamarck, and "Wood" are this species. Not uncommonly dredged in the Gulf of Mexico. Folystira telle a Dall Delicate Giant Turret Plate 1 3m Off southeast Florida. 3 to 3% inches in length. Grayish white. Sculpture not so distinct nor so smooth as in albida. Not uncommonly dredged off Key West. Do not confuse this and the preceding species with Fiisinus couei (pi. 13d). Subjamily COCHLESPIRINAE Shell with a long canal. Sinus on the shoulder, rounded, broad and shal- low to rather deep. Operculum variable. Radula with 2 strong marginals and a very large central. Shell thin with a sharply angled periphery. Genus Ancistrosyrinx Dall 1881 Ancistrosyrifix radiata Dall Common Star Turret Figure 576 South Florida, the Gulf of Mexico and the West Indies. ^ inch in length. A delicate, glossy, translucent and highly ornamented species. Anterior canal very long. Shoulders keeled, with numerous, small, sharp, triangular spines. Commonly dredged from 30 to 170 fathoms. A. elegans Dall (Elegant Star Turret) from about 200 fathoms off Key West is 2 inches in length, more elongate, with more numerous and duller spines on the sharp shoulder. Very rare. Subfamily CLAVINAE Shell between Y^ and /4 inch in length, spire tall and the anterior canal short. Sinus on the shoulder, moderately to deeply U-shaped, often rendered subtubular by a parietal tubercle. Operculum with an apical nucleus. Radula variable. Genus Crassispira Swainson 1840 Crassispira ebenina Dall Dall's Black Turret Figure 57) Southeast Florida and the West Indies. 3/ 4 inch in length; a solid brown-black in color and with a slight sheen.