The Regulative Action of Birds upon Insect Oscillations. 
7 
The catbird had shown its usual preference for ants, eating four- 
teen per cent, of these insects. These birds had taken an unusual 
number of Ooleoptera, which made more than half the food, 
chiefly Scarabaeidae. About two-thirds of them belonged to the 
single species ( Anomala binotatd) mentioned above under the 
food of the robin. Three of these birds had likewise eaten large 
June bugs. Elateridae and their larvae occurred only in trivial 
quantities, while Carabidae amounted to four per cent., chiefly 
Anisodactylus. As in the robin, Diptera, Orthoptera, and Arach- 
nida, were not represented in the food. 
Harporhynchus rufus, L. Brown Thrush. 
This bird was not common in the orchard, and only four speci- 
mens were taken. The food of these was entirely animal, an 
unexpected circumstance, as the brown thrush usually feeds 
largely upon grain. Six per cent, of the food consisted of 
thousand-legs, and insects made the entire remainder. Lepidop- 
tera were about one-fifth of the food, and half of these were 
canker-worms. Like the preceding species, this bird had eaten 
an enormous number of beetles, which amounted to two-thirds of 
its food. Twelve per cent, of the whole was Carabidae, chiefly a 
species of Chlaenius. Scarabaeidae stand at forty-four per cent., 
largely Diplotaxis, Melolontha, and Anomala. Six per cent, were 
Elateridae, and three per cent. Rhynchophora. No specimens of 
the remaining orders had been eaten by these birds. 
Summary of the Family. 
Treating, now, of the twenty-seven thrushes mentioned as one 
group, we find that none of them had eaten any vegetation what- 
ever; that ninety-six per cent, of their food consisted of insects 
(myriapods and earth-worms making up the remaining four per 
cent.); that sixteen per cent, was canker-worms; and only four 
per cent, predaceous beetles. The Anomala previously men- 
tioned made just a fourth of their entire food, other Scarabaeidae 
bringing up the average of that family to thirty-eight per cent. 
Click beetles (Elateridae) with their larvae were five per cent, of 
the whole,, and snout beetles (Rhynchophora) two per cent. 
