162 ILLINOIS ACADEMY OF SCIENCE 
27. P. coccinea (Conrad)—Monticello, Piatt Co., and Hil- 
lery, Vermilion Co. Fairly abundant at Monticello, in soft 
mud and usually seeking the deeper waters. 
GENUS FUSCONAIA Simpson, 1900 
28. I. rubiginosa (Lea)—White Heath, Monticello, St. 
Joseph, Homer Park, Muncie and Hillery. Very abundant; 
prefers the deeper waters, any kind of bottom. 
GENUS QUADRULA (Rafinesque, 1820) Agassiz 
Section Quadrula s. s. 
29. @Q. cylindrica (Say)—Hillery, Vermilion Co., Dr. J. D. 
Hood, collector. Rare at this place; typical of Wabash River 
drainage. 
Section Theliderma (Swainson, 1840) Simpson 
50. @. metanevra (Rafinesque)—Deep waters of the Middle 
Fork at Hillery, Vermilion Co. Rare. 
31. @Q. pustulosa (Lea)—White Heath and Monticello, Piatt 
Co. This is another of the abundant and typical species of the 
Illinois River at Havana; it prefers muddy bottoms, but is 
often found among rock and sand. 
GENUS AMBLEMA Rafinesque, 1819 
32. A. undulata (Barnes)—In all three counties; very 
abundant. In streams and rivers of all depths, usually with 
muddy bottoms. Young shells are often deformed by cow hoofs. 
None of the closely related species, A. plicata and Megalonaias 
heros were found, although at Havana, Illinois, they are quite 
abundant. 
GENUS ROTUNDARIA (Rafinesque, 1820) Simpson | 
33. R. granifera (Lea)—Only one dead valve was found at 0 
Hillery, Vermilion Co. It is very typical. The species proba- 
bly inhabits the deeper waters. 
Order Teleodesmacea 
Superfamily Cyrenacea 
Family Spheriide 
GENUS SPH@RIUM Scopoli, 1777 iP 
34. S. occidentale (Prime)—Muncie, Vermilion Co., in soft 
mud of ponds and bayous, or cut-offs; abundant wherever the 
