Page:American Seashells (1954).djvu/376

shallow suture bearing axial ridges, and with the shoulder of the outer lip bearing a small, triangular projection. Uncommonly collected. Family CAVOLINIDAE Shell symmetrical (not coiled), fragile, white to brown, and of various shapes — needle-like, cylinder-shaped, flattened triangular or bulbous. Genus Creseis Rang 1828 Shell a long cone, almost circular in cross-section, needle-like. Creseis acicida Rang Straight Needle-pteropod Figure 6411 Atlantic and Pacific, pelagic. (N. Lat. 48° to S. Lat. 40°). 20 to 33 mm. (about an inch) in length. A long, straight, slender cone tapering to a sharp point. Styliola vitrea Verrill and conica Esch. are this species. Creseis virgula Rang Curved Needle-pteropod Figure 64P Atlantic and Pacific, pelagic. (N. Lat. 41° to S. Lat. 35°). 8 to 10 mm. in length. A drawn-out, slender shell similar to acicula, but with its narrow end hooked to one side. The amount of bend of hook is variable. Hyalaea conijormis Orb. and Cleodora virgula Soul, and Eyd. are the same. Genus Styliola Lesueur 1825 Styliola siibula Quoy and Gaimard Keeled Clio Figure 64-0 Worldwide in warm seas, pelagic. 10 mm. in length, conical, straight, considerably elongated. The surface is smooth, and with a dorsal groove not parallel to the axis of the shell, but slightly oblique, turning from left to right, with only the anterior extremity (which ends in a rostrum) in the median line. There is only one species in the genus and it is world-wide in distribution. Genus Hyalocylis Fol 1875 Hyalocylis striata Rang Striate Clio Worldwide m warm seas, pelagic.