The Regulative Action of Birds upon Insect Oscillations. 
15 
and Coleoptera to a little more than another fourth. Of these, Cara- 
bidae made four per cent., Cerambycidae two, Rhynchophora one, 
and Anomala binotata fourteen. 
TYRANNIDJE. Flycatchers. 
Tyrannus carolinensis, L. Kingbird. 
This species was not uncommon, but only three were shot. 
Two of these, to my surprise, were found to have eaten canker- 
worms, which made more than a fourth of the food of the whole. 
Five per cent, of the remainder consisted of undetermined Hem- 
iptera, and all the balance was Coleoptera. Seven per cent, was 
Elateridae, two Lampyridae, and more than fifty-eight Scarabaei- 
dae, all Anomala except thirteen per cent, of Aphodius inquina- 
tus , eaten by one of the birds. 
CONTOPUS VIRENS, L. WOOD PEWEE. 
Three of these were shot, none of which had taken canker- 
worms. Their food consisted chiefly of flies and gnats, which 
amounted to fifty-five per cent. Thirteen per cent, of Aphodius 
and ten per cent, of Ips, with a few ants and other Hymenoptera, 
are also worthy of mention. 
Empidonax trailli, Aud. Traill’s Flycatcher. 
Two specimens, shot in 1882, had eaten only insects, one-fourth 
of which were canker-worms, and one-third Ichneumonidae. 
Another fourth consisted of Coleoptera, nearly half of which 
were Anomala; and ten per cent, were ants and other Hymenop- 
tera. 
Empidonax flaviventris, Bd. Yellow-bellied Flycatcher. 
A single specimen had eaten a number of Lepidoptera and . 
their larvae, but no canker-worms. Half the food was Coleoptera, 
nearly all Aphodius and Anomala binotata , — fifteen per cent, and 
twenty-five per cent, respectively. The little Psenocerus was 
likewise taken by this bird, and a specimen of Hymenarcys 
(Hemiptera). 
