SB 
818 
C3576 
ENT 
CIRCULAR No. 93. Issued August 22, 1907. 
United States Department of Agriculture, 
BUREAU OF ENTOMOLOGY. 
L. O. HOWARD, Entomologist and Chief of Bureau. 
THE SPRING GRAIN-APHIS OR SO-CALLED “ GREEN BUG.” 
(Toxoptera graminum Rond.) 
By F. M. WEBSTER, 
In Charge of Cereal and TForage-Plant Insect Investigations. 
The early history in America of the spring grain-aphis (figs. 1, 2 
b } ee p £ 
which has come to be generally known as the “ green bug,” was pub- 
lished in Circular No. 85 of this Bureau, and need not be reproduced 
here. Suffice it to say that it is an imported species, long known to be 
destructive to growing grain in Europe, but not known in this country 
fo} (==! a , “ 
prior to 1882, and not as a destructive insect until 1890. The litera- 
Fic. 1.—The spring grain-aphis or “green bug” (Toxroptera graminum) : a, wingless fe- 
male; b, larva; c, pupa. Much enlarged (from Pergande). 
ture relating to this, the third and perhaps most destructive outbreak 
of the pest, is so misleading that this publication seems necessary in 
order to prevent misapprehension among farmers, and to afford them 
all possible helpful information in advance of future similar out- 
breaks. 
4631—No. 93—07——1 
