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IOWA ACADEMY OF SCIENCE 
Fig. 1. Acorns. (See p. 83.) 
Quercus imhricaria Michx, The four left-hand figures in the lower row. 
Quercus palustris DuRoi. The four right-hand figures in the lower row. 
Quercus hnhricaria x palustris. . The upper row. 
Fig. 2. Leaves. (See p. 83.) 
Quercus imhricaria x palustris. Three leaves showing variation in form. 
