PLATE 2 
A. —Setae of Aphis maidis penetrating the epidermis of young com leaf. 
B. —Same serae shown in A. This illustrates the copious salivary secretion. 
C. —Same setae shown in A and B. An exploratory puncture to the xylem^is 
indicated by the saliva sheath at the left. The setae bundle was withdrawn part way 
and again advanced toward the phloem. 
