aad — 
IY 
parasites in advance of an invasion of this character from the 
South, as was the case in Kansas in May, 1907, has indicated that 
such introductions were not possible and that to attempt it was veri- 
tably “ carrying coals to Newcastle.” 
Female individuals of Lysiphlebus from the cabbage aphis (Aphis 
brassicae L.) taken in the field were first allowed to parasitize Toxop- 
tera and from the latter the adults were obtained. This experiment 
was several times repeated. Females of Lysiphlebus reared under 
cover from the corn root-aphis (Aphis maidi-radicis Forbes) were in 
two cases allowed to parasitize Toxoptera and adults obtained. Fe- 
males of Lysiphlebus were taken from Ap/is setariw in the field and 
the issuing parasites in two cases allowed to parasitize Toxoptera and 
adults secured. This experiment also was repeated several times. 
Female individuals of Lysiphlebus were taken from the corn leaf- 
aphis (Aphis maidis Fitch) in the field and the adult parasites per- 
mitted to parasitize Toxoptera, from which finally the adults emerged. 
This experiment was repeated several times. female specimens of 
Lysiphlebus were taken from the cotton or melon aphis (Ap/ds 
gossypii Glov.) from 
New Mexico and given 
Toxoptera as a host, the 
adult parasites develop- 
ing successfully there- 
from. Female specimens 
of Lysiphlebus were 
taken from Aphis se- 
tarie in the field and 
ee Re crainaphle, Much enlarged, (OrfEViak) 
host, their offspring 
transferred to A. maidi-radicis, and the next generation transferred 
back to Toxoptera. Female individuals of Lysiphlebus were taken 
from A. setariw in the field and allowed to parasitize Toxoptera, their 
offspring transferred to A. setariw, the next generation to Toxoptera, 
and the following generation to A. brassicw, from which adults were 
secured. 
In many cases these breedings were reversed. The only cases of 
failure were in attempting to transfer Lysiphlebus issuing from 
Toxoptera to Chaitophorus and in transferring Lysiphlebus issuing 
from Toxoptera to Iacrosiphum rudbehiew. These experiments were 
reversed with the same results. 
The female goes about, if in grain fields, among the plants, and 
when she finds an aphis she quickly throws her abdomen underneath 
her body and between her legs and with a springlike motion thrusts 
her ovipositor into the body of the aphis (fig. 8), leaving therein a 
[Cir. 93] 
