116 
ducted about 200 experiments in order to gain some definite informa- 
tion on this point. Their mode of procedure was to search out differ- 
ent species of parasitized aphidids in the fields, rear the adult para- 
sites, and breed them into Toxoptera graminum; then, if possible, 
breeding them again into the original host. One attempt, if unsuc- 
cessful, was not considered sufficient, several trials being made. 
While conducting these experiments, other species of parasites were 
found that would breed into Toxoptera also. These will be dealt 
with in their proper places. In all of these breedings, both parent 
and offspring were kept separate and preserved for future study. 
It was found that Aphidius testaceipes would breed interchangeably 
from Toxoptera into Aphis setaride, Aphis maidis, Aphis middletoni 
Thos., 1 Aphis gossijpii, and a species of Chaitophorus. This is the same 
as the list published by the senior author in the Annals of the Ento- 
mological Society of America, 2 with the exception that Chaitophorus 
is added and Aphis orassicse has been expunged from the list, as it 
has been learned that the .species of parasite that would interchange 
with Toxoptera graminum and A. orassicsc is another species of Aphi- 
dius. 
Besides the above fist of interchangeable breedings, Aphidius 
testaceipes has been reared from Aphis oznotherx at Salisbury, N. C, 
by Mr. R. A. Vickery; from A. medicaginis at Wellington, Kans., by 
Messrs. Kelly and Urbahns; from A. rumicis at Clemson, S. C, by 
Mr. G. G. Ainslie; from Macrosiphum viticola at Wellington, Kans., 
by Mr. Kelly; from M. granaria at Spartanburg, S. C, by Mr. 
G. G. Ainslie; from Melanoxantherium sp. at Leavenworth, Kans., 
by Mr. Kelly; from Macrosiphum sp. on black gum (Nyssa sylvatica) 
at Salisbury, S. C., by Mr. Vickery ; from Aphis avenx, at Salisbury, 
N. C, by Mr. Vickery; at Leavenworth, Kans., by Mr. Kelly, and at 
Washington, D. C, by Mr. C. N. Ainslie; and from Aphis medicaginis 
by Mr. J. T. Monell, at St. Louis, Mo. Aphidius testaceipes has also 
been reared from several unidentified species of aphidids, as follows: 
From an aphidid on Ampelopsis sp. by Mr. C. N. Ainslie; from an 
aphidid on Capsella sp. at Wellington, Kans., by Mr. C. N. Ainslie ; from 
an aphidid on Kochia scoparia at Rochester, Minn., by Air. C. N. Ainslie ; 
from an aphidid on locust at Wellington, Kans., by Mr. Kelly; from 
an aphidid on plum at Salisbury, N. C, by Air. Vickery; from an 
aphidid on pigweed (Chenopodium album) in Olms tead County, Minn., 
by Mr. C. N. Ainslie. 
Further addition to this fist of hosts may be made by citing the 
hosts of some of the synonyms of Aphidius testaceipes. 3 We will deal 
i Aphis middletoni can not be satisfactorily separated from Aphis maidi-radicis and when found on any 
other plant except Erigeron it has usually been identified as Aphis maidi-radicis. (See Bui. 85, Bur. 
Ent., U. S. Dept. Agr., pp. 113-114. Contributions to a Knowledge of the Corn Root-Aphis, by R. A. 
Vickery .) 
2 Ann. Ent. Soc. Amer., vol. 2, No. 2, pp. 67-87, June, 1909. 
3 See Proc. U. S. Nat. Mus., vol. 11, pp. 665-S69, 1888. 
F< 
