North American Land Snails 



of seven whorls, with teeth on both outer and inner Hps. Dia- 

 meter J to J of an inch. Sante Fe, N. M. 



THE WHITE-LIPPED SNAILS 

 Genus POLYGYRA, Say 



Shell many-whorled, globose to flat-coiled, keeled or rounded, 

 plain or banded; aperture plain or obstructed by three teeth; 

 lips reflexed; foot long, narrow, granulated. 



A large genus including Triodopsis and Mesodon of Rafi- 

 nesque. Its distribution centres in eastern North America, 

 but there are several western species. 



The White-lipped Snail (P. alholabris, Say), familiar to 

 many under the old name, Helix, or the newer one, Triodopsis, 

 or by any other, in fact, is still the same old horny yellow, white- 

 lipped snail, known by all woods rovers with an eye for the small 

 people who live under dead leaves and under prostrate, decaying 

 logs. The spire is slightly elevated above the large, fifth whorl, 

 whose rim is the thick, flanged white lip. Excess of white enamel 

 fills the central pit, and a nodule of it forms a tooth on the inner 

 lip. The only sculpture on the outside is the growth striation. 



The long, slender, mottled body, the four " horns," the longest 

 bearing the black eyes, the graceful movements and the "moon- 

 glittering trail" — all are sources of wonder and delight to children 

 of all ages. Yet how many foolish grown-ups have inherited or 

 acquired the aversion credited to the four-and-twenty tailors! 

 Diameter, i inch. Eastern states. 



P. Townsendiana, Lea, a handsome pitted snail, is yellowish 

 brown, often mottled, and finely striated, with a thickened white 

 peristome, shaped like a horseshoe, and no teeth to be seen. 

 Diameter, f inch. Oregon and Washington. 



P. devia, GId., solid, six-whorled, brownish, low-spired, 

 has a white lip, bent outward, and a tooth on the inner wall of 

 the aperture. Several varieties occur in Oregon and Idaho. 

 Diameter, J to i inch. 



P. Chiricahuana, Dall, is a thin, glossy brown orb-shell, 

 deeply pitted, with a simple, toothless aperture, and a white 

 strongly reflected lip. It is § inch across. 



Habitat. — Arizona and New Mexico. 



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