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Family Helicidae — Part 1

SHELL top-shaped, globose or depressed; aperture semi-lunar; columella callous; lip thick; operculum not spiral, made of overlapping plates. Head bearing a stout, blunt proboscis; foot long; radula long, narrow; jaw absent. A tropical family of several genera, living in damp situations in forests.

Genus HELICINA, Lam.

Characters of the family. Three hundred and fifty species. Distribution, world-wide.

H. orbiculata, Say, is a tiny globular shell, brownish yellow, sometimes spotted, with a thick white lip. The operculum folds back upon the columella as if hinged to it when the animal is gliding along. Diameter, 1/3 inch.

Habitat.--Tennessee to Texas and Florida.

H. agglutinans, Sby., has a depressed shell and a single keel, decorated with frond-like processes. The inner lip is much thickened. Diameter, 3/4 inch.

Habitat.--Philippines.

H. Briarea, Poey., has a flattened dome almost covered with brown, but white below and at the sutures. The wide aperture is white and polished. Diameter, 1 inch.

Habitat.--Cuba.