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i] 
N 
EXPLANATION OF PLATES X-XII 
Fic. 1.—Rubus strigosus Michx.: transverse section of anther showing 
aera perfect pollen; xX 125. 
Fic. 2.—R. neglectus Peck: transverse section of anther showing pollen 
to be reer sterile; K 125. 
G. 3.—R. peglocius Peck: more highly magnified view of fig. 2; X 300. 
re Ic. 4.—R. odoratus L.: transverse section of anther showing morpho- 
logically athect pollen; X12 
IG, 5.—K. dleshoniéasis: Porter: transverse section of anther showing 
morphologically perfect pollen; 125. 
