THE MOLLUSCA 



OP 



MUSCATINE COUNTY AND VICINITY, 



HELICID^l. 



HELIX. 



H. arborea, SAY. Abundant wherever any protection from the 



sun is afforded. Seems to be somewhat gregarious ; 20 to 30 



sometimes found together in hibernation. Greatest diam., 



6.6 ; least, 5.6 ; height, 3 mm. 

 H. viridula, MENKE. Very rare. Found with arborea,- from 



which it is difficult to clearly distinguish it. Greatest diam., 



5 ; least, 4.3 ; height, 2 mm. 

 H. minuscula, BINNEY. Somewhat rare. In all damp woods, in 



mould about logs and stumps. Greatest diam., 1.8; least, 



1.6 ; height, .8 mm. 

 H. fulva, DRAPARNAUD. Rare. Wide-spread in damp woods. 



Shell fragile. Greatest diam., 2.4 ; least, 2 ; height, 1.4 mm. 

 H. lineata, SAY. Rare. Widely distributed ; damp woods and 



deep ravines. Greatest diam., 3.8; least, 3.6; height, 1.4 



mm. 

 H. eoncava, SAY. Rather rare. Wyoming Hills ; Cedar River 



bottom ; railroad one mile north of Muscatine ; one mile 



above Drury's Landing, along foot of bluff, in Illinois. 



Greatest diam., 16 ; least, 13 ; height, 6.5 mm. 

 H. alternata, SAY. Common. In loam in woods. Greatest 



diam., 21 ; least, 18 ; height, 10 mm. 

 H. perspectiva, SAY. Very rare. Only two specimens have been 



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