Page:American Seashells (1954).djvu/205

Rh % to /4 inch in length, not elongate. Apertural side of body whorl sometimes flat, i to 2 former varices on last whorl. 3 or 4 spiral rows of even-sized fine beads on the whorls of the spire. Color dark brown-black, but sometimes whitish with heavy specklings and mottlings and bands of reddish brown. Very common under rocks in warm water. Do not confuse with Batillaria ininwia (see above). Genus Bittium Gray 1847 Shell small, very slender, spire high and body whorl small. Whorls varicose. Nucleus of about 3 glassy, smooth whorls. Aperture ovate, the anterior canal broad and stout. Subgenus Bittiwn s. str. Bittiu?7i altematiim Say Alternate Bittium Gulf of St. Lawrence to Virginia. Adults very small, % to /4 inch in length, light- to dark-brown in color, sometimes translucent or with specklings. Suture impressed, whorls rounded. Sculpture on top whorls either cancellate or with 4 to 5 spiral rows of beads, or occasionally with axial, nodulated ribs. Base with small spiral cords. Outer lip flaring, thin and sharp. Columella short, twisted at the base and stained brown. Very abundant from tidal flats to 20 fathoms. B. virginicuffi Henderson and Bartsch from Chincoteague, Virginia, is similar, but very elongate, more whorls, with a much more flaring and basally projecting lip, and with a large, whitish, former varix on the body whorl. Bittium variimt Pfeiffer Variable Bittium Plate 191 Maryland to Florida, Texas and Mexico. Adults similar to altematiim, but smaller (% inch), nearly always with a former, thickened varix. The aperture is proportionately smaller and the base of the apertural lip is squarish instead of rounded. The last third of the body whorl is generally destitute of sculpturing. Common in eel-grass just below low tide. Subgenus Stylidium Dall 1907 Bittium eschrichti Middendorf Giant Pacific Coast Bittium Alaska to Crescent City, California.