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Rh $3/4$ to 1 inch in length, very similar to N. tessellata, but with a lighter-colored, yellowish gray operculum. The spiral ridges on the shell are more numerous, the color patterns blurred, the aperture relatively wider, and the teeth more prominent. This is a salt to brackish-water inhabitant of protected shores, and is abundant only in certain restricted localities. It is seldom represented or properly labeled in private collections.

$1/3$ to $1/2$ inch in length, thin, smooth, chalky-white with black, axial, zebra-like stripes. Aperture and smooth operculum light-yellow. Lives in small, placid pools above the high-water mark. Common in the West Indies, rare in Florida.

$1/2$ inch in length, smooth, glossy, very variable in color pattern and shades—blacks, browns, purples, reds, whites, olive—crooked lines, dots, mottlings, zebra-like stripes and sometimes spirally banded. Parietal area smooth, convex, white to yellow, and with a variable number of small, irregular teeth. Operculum usually black. A very common, widespread inhabitant of intertidal, brackish-water flats.

$1/2$ inch in length, glossy, often with the spire eroded away. Ground color brownish green, olive or brownish yellow with numerous axial lines of black-brown or lavender. Operculum black to slightly brownish. Common in brackish water and also found in fresh-water springs near the seashore in Florida.

A globose form or subspecies (?) with a short spire and more convex whorls replaces the higher-spired, typical form from Texas to Panama, but