6 The Regulative Action of Birds upon Insect Oscillations. 



lowing year. The food was wholly animal, neither fruit nor any 

 other kind of vegetation having been taken by any of the birds. 

 Only three of the above number had eaten canker-worms, which 

 composed, as nearly as could be estimated, about one-fifth of the 

 food of the entire group. Insects made ninety-three per 

 cent., the remainder consisting of a common species of my- 

 riapod (five per cent.), earth-worms, and gasteropod mol- 

 lusks. Ants were eaten by these birds only in trivial 

 numbers. Diptera, Orthoptera and spiders were conspicuous 

 by their entire absence. Cut-worms were extraordinarily 

 prominenj in the food, making twenty-eight per cent, of the 

 whole. Half of them consisted of a single large, injurious 

 species {Nephelodes violatu). Among the Coleoptera, which 

 amounted to thirty-six per cent, of the whole, the Scarabtuidae 

 and Elateridae were the principal elements, the former represented 

 by eighteen per cent., and the latter by eleven. Among the Scar- 

 abseidae was a species known as a vine leaf-chafer {Anomala 

 binotata), which made fourteen per cent, of the food. This in- 

 sect was scarcely less abundant than the canker-worm, and 

 appeared in extraordinary numbers in the food of nearly all the 

 species of birds examined, although it had not attracted the atten- 

 tion of the owner of the grounds. I searched a small vineyard ad- 

 jacent, but saw no signs of unusual injury to the leaves. Carabidas, 

 although common in the orchard, had scarcely been touched by 

 the robins, only a single specimen of the family occurring. 

 Hemiptera were found but in trivial numbers, representing about 

 equally the families Coreidae and Cydnidse. Hymenoptera were 

 still less abundant, composing only one per cent, of the food. 



MiMUS CAROLINENSIS, L. CaTBIED. 



This species was very common, and thoroughly at home among 

 the trees, where it was doubtless nesting. Fourteen specimens 

 were taken, three at the first visit and eleven at the second. 

 With the exception of two per cent, of myriapods, their food con- 

 sisted entirely of insects. Canker-worms had been eaten by eight 

 of the birds, but not in any great number, as they composed but fif- 

 teen per cent, of the food of the species. A few cut- worms had 

 been taken, and a larger number of other caterpillars, bringing 

 the total for Lepidoptera up to about one-fourth of the food. 



