12 



THE SPRING GRAIN-APHIS OR " GREEN BUG." 



contributed more or less to our knowledge of the pest and its natural 

 enemies, and throughout the following pages credit has been given 



Fig. 1. — The spring grain aphis ( Toxoptera graminum): Wheat plant showing winged and wingless 

 viviparous females with their young clustered on the leaves, and a few parasitized individuals on lower 

 leaves. About natural size. (Original.) 



each individual where possible to do so. For a critical, technical 

 study of the parasites of the species, credit should be given Mr. J. C. 

 Crawford, assistant curator, Division of Insects, U. S. National 



