240 



ENTOMOLOGY 



the present tense. About two thirds of the food of birds consists of 

 insects. 



Robin. The food of the robin in Illinois, from February to May in- 

 clusive, consists almost entirely of insects; at first, larvae of Bibio albi- 

 pennis for the most part, and then caterpillars and various beetles. When 

 the small fruits appear, these are largely eaten instead of insects; thus 

 in June, cherries and raspberries form fifty-five per cent, and insects 

 (ants, caterpillars, wireworms and Carabidae) forty-two per cent, of the 

 food; and in July, raspberries, blackberries and currants form seventy- 

 nine per cent, and insects (mostly caterpillars, beetles and crickets) but 

 twenty per cent, of the food. In August, insects rise to forty-three per 

 cent, and fruits drop to fifty-six per cent., and these are mostly cherries, 

 of which two thirds are wild kinds. In September, ants form fifteen 

 -per cent, of the food, caterpillars five per cent, and fruits (mostly grapes, 

 mountain-ash berries and moonseed berries) seventy per cent. In 

 October, the food consists chiefly of wild grapes (fifty-three per cent.), 

 ants (thirty-five per cent.), and caterpillars (six per cent.). 



For the year, judging from the stomach contents of one hundred and 

 fourteen birds, garden fruits form only twenty-nine per cent, of the food 

 of the robin, while insects constitute two thirds of the food. The results 

 are confirmed by those of Professor Beal in Michigan, who found that 

 more than forty-two per cent, of the food of the robin consists of insects 

 with some other animal matter, the remainder being made up of various 

 small fruits, but notably the wild kinds. 



Upon the whole, the robin deserves to be protected as an energetic 

 destroyer of cutworms, white grubs and other injurious insects, and the 

 comparatively few cultivated berries that the bird appropriates are 

 ordinarily but a meagre compensation for the valuable services rendered 

 to man by this familiar bird. 



Catbird. Not so much can be said for the catbird, however, for, 

 though its food habits are similar to those of the robin, it arrives later 

 and departs earlier, with the result that it is less dependent than the 

 robin upon insects and that berries form a larger percentage of its 

 total food. 



In May, eighty-three per cent, of the food of the catbird consists of 

 insects, mostly beetles (Carabidae, Rhynchophora, etc.), crane-flies, 

 ants and caterpillars (Noctuidae) ; while dry sumach berries are eaten to 

 the extent of seven per cent. For the first half of June, the record is 

 much the same, with an increase, however, in the number of May 



