Page:American Seashells (1954).djvu/199

Rh shell, cutting across the ribs. Lip of aperture with one or two swollen axial rings.

Rather thick, glossy, slightly curved shells; aperture minutely constricted; sculpture absent except for microscopic growth lines. The shells are larger, heavier and not as bulbous as those in the subgenus Fartulum.

About 4.5 mm. in length, glossy, cream-white. Smooth except for microscopic growth lines. Apical plug sunk in at the posterior end of the shell and with a sharp, horn-like projection. Aperture minutely constricted.

Shells very small, about 2 mm. in length, fragile, smooth, except for microscopic growth lines; not swollen in the middle; and with a nonconstricted aperture facing to one side (oblique).

1.5 to 2.0 mm. in length, fragile, translucent-tan with opaque-white mottlings. Not swollen in the center. Aperture oblique. Apex with a lopsided plug which has a single, weak spur. Found under flat rocks imbedded in tough, sticky marl.

2.0 to 2.5 mm. in length. Smooth, except for fine, circular scratches. Shell stubby, slightly compressed laterally; aperture oblique; apical plug dome-shaped. Color translucent-tan to yellow-brown. Moderately common.

2.2 to 3.5 mm. in length. Smooth, except for fine, circular scratches. Shell elongate, round in cross-section. Aperture moderately oblique; apical