Plate I 



AECIA, AECIOSPORES, AND PERIDIAL CELLS OF G. J TJNIPERI- VIRGINIAN AE, G. GLOBOSUM, AND 



G. GERMINALE 



1, Apple rust (right) and hawthorn rust (left) on leaves of wild apple 



2, Aecia of G. globosum on a leaf of the Tolman Sweet variety 



3, Peridial cell and aeciospores of G. juniperi-virginianae. X 160 



3 A, Germinating aeciospores oi G. juniveri-tirginianae 



4, Peridial cells and aeciospores of G. globosum. X 160 



4 A, Peridial cells and aeciospores of G. globosum. X 275 



5, Peridial cells £.nd aeciospores of G. germinale. X 275 



6, Aecia of G. juniperi-virginianae on leaf of cultivated apple 



