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IOWA ACADEMY OP SCIENCE 
Explanation op Plate XT. 
Fig. 1. A loess-covered paha ridge northeast of North Liberty. Iowa. The part to 
the left (north) is sandy below yellow loess. In part to right, and south- 
ward, Devonian limestone forms the core, and is capped with Kansan drift 
and two loesses, the lower gray, the upper yellow. (See p. 119.) 
Fig. 2. A stubble field to the left which has caught the snow and soine fine soil 
from the plowed field to the right. Shows the retaining power of vegetation. 
Calmar, Iowa. (See p. 122.) 
