66 ILLINOIS BIOLOGICAL MONOGRAPHS [164 
64. Galba obrussa (Say). 
Obrussa occurs in Stony Creek near Muncie, collected by Mr. John R. 
Malloch, May 29, 1919. The specimens are typical though small. 
65. Galba caperata (Say). 
This species occurs abundantly in swampy woodlands bordering the 
Salt Fork about three miles north of Urbana, the ground in dry weather 
being almost paved with the dead shells of this snail. Some of the snails 
escape the dry period by crawling into cracks and holes and there hiber- 
nating. This species has not been found in or near Salt Fork or the other 
tributaries of the Big Vermilion River. Because of its preference for small, 
summer-dry ponds and pools this Galba will not be found, probably, in any 
part of the streams herein considered. 
