The Chrysalis Shells and Door Shells - Family Pupillidie Pupidie

THE CHRYSALIS SHELLS AND DOOR SHELLS - FAMILY PUPILLIDIE (PUPIDIE).

Shell

cylindrical, many-whorled, usually minute, with con tracted aperture, guarded by teeth, often set with internal lamel la'; apex blunt; radula as in Helix.

A family of minute mollusks.

Megaspira elatior, Spix., a forest snail of Brazil, is excep tional. It bears an auger-shaped shell, 21- inches long, of about twenty-five coils.

Genus PUPILLA, Leach (PUPA, Lam.) Characters of the family. A large genus of universal distri bution. The well-established name, Pupa, of Lamarck is obliged to give place to the earlier one, given by Leach.

The Armed Chrysalis Shell (P. armifera, Say) is almost thimble-shaped; inside the thick, recurved lip the aperture is guarded by numerous teeth and folded plaits. Animal black. Length, inch.

Habitat.— Damp soil about grass plots, or under logs. East ern half of United States. A few other species are found in this country.

Genus VERTIGO, MUll.

Shell minute, ovate, with blunt apex; aperture with four to seven folds; lip expanded, white. Animal as in Pupa, but lacking one pair of tentacles. Distribution world-wide. One hundred species.

V. ovata,

Say, dark amber-coloured, stout. with semi circular, toothed aperture, and only inch long, is scarcely 28o The Chrysalis Shells and Door Shells large enough to catch the eye of the amateur. But it interests

the collector, who has his mind on what of beauty and truth the microscope yields. This tiny mollusk hustles along at an awkward but speedy pace for a snail, alternately setting its snout on a spot and drawing the body up to it. Look for it in wet places along stream banks.

Habitat.— Maine to Texas.

Genus STROPHIA, Alb. (CERION, March.) Shell large, oblong, cylindrical, longitudinally ribbed or costate, solid, white; aperture oval; lip expanded; columella folded. Dentition as in Helix.

S.

incana, Binn., is our only representative of this West Indian genus. It is found on low ground, or under stones, at Key West near tide marshes, and clinging to plants. In winter it secretes an epiphragm of thin membrane. The chalky, solid shell is sometimes streaked with reddish brown. Length, I inch.

Habitat.— Florida Keys.

S. decumana,

Fer., of the Bahamas, has the form of a silk worm's cocoon, but is white, and pierced by a tubular umbilicus. This is one of the largest species.

S. chrysalis,

Fer., blunt, stout, its flat coils strongly cross ribbed and spotted, is a Cuban chrysalis shell. Length, i inches.