UTILITY OF BIRDS. 61 



who of all persons in the world ought to be the most familiar 

 with the facts that prove their usefulness, are indeed the most 

 ignorant of them ; and they are so full of prejudices against 

 the birds, that they attribute to them a full moiety of the 

 mit-chief perpetrated by insects. There is perhaps not an insect 

 tribe in existence which is not the natural food of some species 

 of the feathered race, and which, if not kept in check by their 

 agency, would multiply to infinity. Calculations have been 

 frequently made, to ascertain the probable amount of insects 

 consumed by single birds. Many of these accounts seem 

 almost incredible ; yet they will, for the most part, admit of 

 demonstration. 



Two different methods have been adopted for the purpose of 

 ascertaining this class of facts ; first, by watching the birds and 

 taking note of their actions ; second, by destroying individuals 

 at different times and seasons, and examining the contents of 

 their alimentary organs, to ascertain the quality of their food. 

 Mr. Bradley, an English writer, mentions a person who was 

 led by curiosity to watch a pair of birds that had a nest of 

 young, for one hour. They went and returned continually, 

 bringing every time a caterpillar to their nest. He counted 

 the journeys they made, and calculated that one brood could 

 not consume less than five hundred caterpillars in the course of 

 a day. The quantity consumed in thirty, at this rate, by one 

 nest, would amount to 15,000. Suppose that every square 

 league of territory contained one hundred nests of this species — 

 there would be destroyed by the birds of one species alone, a 

 million and a half (1,500,000) of caterpillars, in the course of 

 one month for every square league of agricultural territory. 



I was sitting at the window one day in May, when my sister 

 called my attention to a golden robin in a black cherry tree, 

 devouring the common hairy caterpillars ; and we counted the 

 number he consumed while he remained on the branch. The 

 time that elapsed was one minute by the watch, and during 

 this space he destroyed seventeen caterpillars. But it is worthy 

 of notice, that he did not swallow the whole insect. After 

 seizing it in his bill, he carefully set his foot upon it, tore it 

 asunder, and swallowed a small portion taken from the inside. 

 He then seized others in succession, and in like manner selected 

 and devoured his favorite morsel. Had he consumed the 



