NUTHATCHES, TITMICE, CREEPERS, AND WRENS. 107 



devouring insects of many kinds. In a canker-worm infested 

 orchard sixty-one per cent, of the food of two chickadees con- 

 sisted of these caterpillars, while injurious beetles constituted 

 the remainder. 



In a recent investigation of the winter food of the chick- 

 adee, we studied l the stomach contents of forty-one speci- 

 mens taken during November, December, January, February, 

 and March. The results as a whole show that more than 

 half of the food of the chick- 

 adees during winter consists 

 of insects, a very large pro- 

 portion of which are taken 

 in the form of eggs. About 

 five per cent, of the stomach 

 contents consisted of spiders 

 or their eggs. Vegetation of 

 various sorts made up a little 

 less than a quarter of the 

 food, two-thirds of which, 

 however, consisted of buds 

 and bud-scales that were be- 

 lieved to have been accidentally introduced with plant-lice 

 eggs. These eggs made up more than one-fifth of the entire 

 food and formed the most remarkable element of the bill 

 of fare. This destruction of the myriads of eggs of plant- 

 lice which infest the fruit, shade, and forest trees is probably 

 the most important service the chickadee renders during its 

 winter residence. More than four hundred and fifty eggs 

 sometimes occur as the food of one bird in a single day. 

 On the supposition that one hundred were eaten daily by 

 each of a flock of ten chickadees, there would be destroyed 

 one thousand a day, or one hundred thousand during the 

 days of winter, a number which we believe to be far below 



THE CHICKADEE, OR BLACK-CAPPED 

 TITMOUSE. 



1 New Hampshire College Agricultural Experiment Station, Bull. f>4. 



