PAPERS ON ZOOLOGY 181 
Brownfield and Cottonwood Woods the species was abundant, 
usually two individuals found together. This is probably the 
northernmost range of this species; it is very abundant in Ten- 
nessee and Alabama. It seems to prefer a much drier habitat 
than the other Pyramidulas. It was also found under bark of 
standing trees. On one occasion it was collected under a 
boulder in the glacial drift near Hillery. At this same town, 
a dozen specimens were found under the bark of a single log. 
It associates with other Pyramidulas, and with the Poly- 
gyrine and Zonitide. 
GENUS HELICODISCUS Morse, 1864 
115. H. parallelus Say—At all localities in the three coun- 
ties. It is plentiful in places, usually found in the crevices of 
the bark, under logs, in loose, crumbly soil, etc., preferring cool 
situatious either moist or wet. It is very rare in the dry, open 
areas. It associates with the majority of the smaller forms. It 
appears to be subterranean in habits. The animal is very shy, 
its movements very slow. The shell is carried almost flat. In 
eating it nibbles at the surface of leaves, resembling in this 
respect the work of certain leaf skeletonizers of the insect 
realm. 
Subfamily Punctine 
GENUS SPHYRADIUM Charpentier 
116. 8S. edentulum Draparnaud—Brownfield Woods, rare; 
only three specimens were found in three and one-half years. 
These were under logs of moderate size, and in the interstices 
of bark, associated with Gastrocopta contracta. 
LITERATURE CITED 
Baker, Dr. Frank C. The Mollusca of the Chicago Area, Pt. 
1898 1, Pelecypoda. Bulletin III, Nat. Hist. Surv., The Chi- 
cago Academy of Sciences. 
1902 The Mollusca of the Chicago Area, Pt. 2, Gastropoda. 
Bulletin III, Nat. Hist. Surv., The Chicago Acad. Sci. 
1906 A Catalog of the Mollusca of Illinois. Bulletin III, 
State Lab. Nat. Hist., vol. VII, Art. VI. 
1911 A Monograph of the Lymneidi. Special Bulletin, The 
Chicago Academy of Sciences. 
