utina. Early whorls purplish brown, last whorl translucent, light chestnut-brown. Shell covered by a thin varnish of periostracum of the same color. At the edge of the thin, smooth outer lip, the periostracum is neatly curled back to form a minute ridge. Umbilicus slit-like, with the periostracum puckered along its length. Operculum littorinid, and is withdrawn well within the glossy-brown aperture. Not uncommon in shallow water.
Genus Littorina Ferussac 1821
Plate 19b
3⁄4 to 1 inch in length, thick, smoothish. Gray to brownish gray in color. Inside of aperture chocolate-brown. Columella and inner edge of aperture whitish. In young or perfect specimens there are fine, irregularly spaced, spiral threads with microscopic, wavy wrinkles in between. Introduced from Europe some time before 1840. A favorite food in Europe. Very common along the rocky shores of New England.
Plate 19c
New York to north Florida to Texas.
About 1 inch in length, thick-shelled, with numerous, regularly formed spiral grooves. Outer lip strong, sharp, slightly flaring, and with tiny grooves on the inside. Color usually grayish white with tiny, short streaks of reddish brown on the spiral ridges. Aperture yellowish white. Callus of inner lip and the columella pale reddish brown. Commonly found in large numbers among the sedges of brackish water marshes. Not recorded alive south of Indian River (east Florida) or Charlotte Harbor (west Florida).
Plate 19e
South half of Florida to Texas, the West Indies and Bermuda.
Females about 1 inch, males about 1⁄2 inch in length. Shell fairly thick and strong. Base angulate; aperture purplish brown. Columella various shades of dark-brown. Outer shell white to bluish white with many narrow, zigzag, oblique lines of chestnut-brown or purplish brown. Early whorls uniformly pale reddish brown. Female shells: higher than wide, smoothish. Male shells: as high as wide, with strong spiral grooves. Operculum dark-brown. Abundant in crevices between tides in rocky areas. Introduced to the Pacific side of the Panama Canal. Do not confuse with the larger and thinner-shelled L. angulifera whose operculum is light-brown, not dark-brown, in color.
