MISCELLANEOUS ENEMIES. 
135 
Birds. 
Birds devour immense numbers of the spring grain-aphis. Miss 
Margaret Morse, of Clark University, has been kind enough to conduct 
some experiments for us in feeding Toxoptera to quail. She has 
learned that they are very fond of the aphidids and estimates that 
about 5,000 individual Toxoptera were eaten by a single quail in one 
day, preference being shown for those that were unparasitized. 
Mr. W. L. McAtee, of the Biological Survey of the United States 
Department of Agriculture, made some special studies of the aphis- 
eating habits of some of our birds in March- April, 1909, at Winston- 
Salem, N. C, at the time Toxoptera was so destructive in that 
vicinity. He states that in a wheat field of about 
100 acres there were over 3,000 birds present 
daily; sometimes the number ran as high as 8,000 
to 9,000. So large a number of birds would be 
found in the fields only during migration, and />--Z^ff 
even at that time the presence of so many indi- 
cates that they were attracted to the fields by 
the abundant food. In so far as could be ascer- 
tained, about nine-tenths of the birds were feed- 
ing upon aphidids (including Toxoptera graminum, 
MacrosipJium granaria, and Aphis avense), some 
taking as many as 180 at a single meal. These 
aphidids are" very small, soft-bodied insects and 
many meals would be required by a bird in a 
single day to satisfy its hunger. The average 
number per meal was at least 50, and we may 
assume that 6 times this number were taken per 
day. On this basis the number of aphidids de- 
stroyed by birds on the farm daily during the 
migration season is 90,000. Below is a partial 
fist of the species Mr. McAtee found devouring Toxoptera at 
Winston-Salem. A complete list can not be given at this time, 
since his studies are not yet finished; many species will undoubtedly 
be added. 
Goldfinch (Astragalinus tristis). 
Vesper sparrow (Po&cetes gramineus). 
Savanna sparrow (Passerculus sandwichensis savanna). 
Chipping sparrow (Spizella socialis). 
Song sparrow (Melospiza melodia). 
All of these birds occur over the entire South. 
MISCELLANEOUS ENEMIES OF TOXOPTERA. 
Under the head of miscellaneous enemies may be considered ene- 
mies that are of very slight economic importance; those, in other 
words, that have been observed occasionally attacking Toxoptera. 
Fig. 4S.— ApMdoletes sp., 
cecidornyiid larva 
which attacks the 
spring grain-aphis, a 
Larva; b, anterior ex 
t r e in i t y protruded 
showing breastbone; c 
ventral view of poste- 
rior segment, a, Much 
enlarged; b, c, greatly 
enlarged. (Original.) 
