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River Snails

The collector must search for these snails in the clear water of creeks that flow down mountain slopes. The green algae are their accustomed food.

The Virginian Goniobasis (G. Virginica, Gmel.) is slender and long, with about six whorls, rounded a little, and banded with red near the middle and base of each. Some forms are finely ridged throughout, with ten or twenty lines on the body whorl. The tip is always worn off. The colour is dark brown or olivaceous. Length, 1 to 1 3/4 inches.

Habitat.--Delaware and Schuylkill rivers.

The Plaited River Shell (G. plicifera, Lea) has keen-edged folds crossing the whorls to the very apex of its horn-like spire. But for its dark complexion this river shell might be mistaken for one of the ladder shells, though the latter are marine mollusks and decidedly pale. Length, 1 inch.

Habitat.--Oregon.

The Sharp-Lined River Shell (G. acutifilosa, Strns.) bears a double row of sharp tubercles winding up its tall spire, and below these, on the body whorl are four or five plain, sharp keels that very prettily crimp the thin outer lip. The tip is usually missing, else the shell would be over an inch long.

Habitat.--Eagle Lake, Cal.

G. rubiginosa, Lea, is rusty, with spiral keels on all but the smooth body whorl.

Habitat.--Oregon.

G. nigrina, Lea, is black, has smooth, rounded whorls, and is slender. Length, about 3/4 inch.

Habitat.--Tributaries of the Sacramento River.

G. bulbosa, Gld., smooth, and swollen, lives in streams that feed the Columbia River.