North American Land Snails 



widening pit separating its flattened coils. The reddish streaked, 

 horny shell is finely striated. Animal has narrow white foot; 

 head dusky, blue, granulated; eye-stalks slender. Diameter, 

 f inch. 



Habitat. — Northern United States. 



Sub-Genus PATULA, Held 



Shell depressed, top-shaped, with a deep, conical umbiHcus; 

 foot large. A sub-genus of several hundred species; of universal 

 distribution. 



In the eastern states these snails lay eggs; the western 

 species bring forth young alive, probably because of the aridity 

 of the climate; cgg3 laid in the ground would not hatch, owing 

 to drought. 



P. alternata in the East and P. strigosa in the Rocky Moun- 

 tain region, are among our commonest land snails. 



The Alternate Patula (P. alternata, Say) is decorated 

 with interrupted streaks of reddish brown, that often zigzag 

 across the whorls. The shells are thin and transparent, sculptured 

 with close diagonal raised striae. Lip smooth. Found in colonies 

 on decaying logs or in other damp places in woods, or even in 

 city backyards. In winter they are found in pockets. Binney 

 believes this crowding together is for the purpose of preserving 

 bodily warmth. Diameter, i inch. 



Habitat. — Eastern and central United States. 



In P. solitaria, Jay, the large body whorl is banded with 

 three brown lines. It has a deep narrow pit, and a somewhat 

 elevated apex. Habit, solitary. Diameter, i^ inches. 



Habitat. — Central and northwestern states. 



The Streaked or Mountain Snail (P. strigosa, Gld.) is 

 streaked by two brown bands that encircle tha body whorl, the 

 upper one of which winds almost to the apex. In contrast to 

 the translucent flesh tint, a band of opaque white separates the 

 two brown ones. The best place to look for specimens is at the 

 foot of crumbling limestone cliffs. 



This is the commonest snail between the Rockies and the 

 Sierra Nevada. In L'tah and Idaho it is especially abundant. 

 Varieties reach the altitude of 8,500 feet. Naturally the species 

 is variable. Diameter, under i inch. 



Habitat. — Rocky Mountains, western slopes. 



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