126 
that had not previously been parasitized; he experienced no diffi- 
culty, however, in rearing it when the adults were placed in cages 
with aphidids that were brown, having been killed by some species 
of Aphidius. It may be that under certain conditions Megorismus 
sp. is also a primary parasite. Mr. Parks finds that it takes about 
30 days in developing from egg to adult in a temperature of about 
70° F. indoors. 
It has been reared in conjunction with ApMdius sp. from Toxoptera 
graminum and ChaitopTiorus sp. at Wellington, Kans., by Messrs. 
Kelly and Urbahns; from T. graminum and ApJiis Irassicse in the 
same locality by Mr. Parks. Mr. Parks also reared it from Macrosi- 
Fig. 34. — Megorismus sp. r a secondary parasite of the spring grain-aphis: Male, greatly enlarged; female 
abdomen, more enlarged, at right. (Original.) 
phum pisi at Washington, D. C. Mr. C. N. Ainslie reared it from 
Hyalopterus dactylidis in the same locality, and the junior author 
reared it from Myzus persicx at Lafayette, Ind. 
Aphidencyrtus aphidiphagus Ashm. 
The species Apliidencyrtus aphidipJiagus Ashm. (fig. 35) has also 
been considered a primary parasite, and while we have no direct 
evidence to disprove this we very strongly suspect that it is in this 
case a secondary parasite. Like Megorismus, which, we have shown, 
is sometimes, at least, a secondary parasite, we have reared it only 
in conjunction with known primary parasites. Mr. G. G. Ainslie 
could rear it only in connection with Aplidinus sp. from T. graminum 
at Clemson, S. C, and Mr. C. N. Ainslie reared it from Aphis 
