CALCULATIONS. 211 



pillars that would follow the extinction of this single 

 species. 



It is recorded in " Anderson's Eecreations," that a curious 

 observer, having discovered a nest of five young jays, re- 

 marked that each of these birds, while yet very young, 

 consumed daily at least fifteen full-sized grubs of the May- 

 beetle, and would require many more of a smaller size. 

 The writer conjectures that of large and small each bird 

 would require about twenty for its daily supply. At this 

 rate the five birds would consume one hundred. Allow- 

 ing that each of the parents would require fifty, the fam- 

 ily would consume two hundred every day, and the whole 

 amount in three months would be about twenty thousand. 

 This seems to me from my own experience a very mod- 

 erate calculation. 



In obedience to an almost universal instinct, the gra- 

 nivorous birds, except those that lead their brood around 

 with them like the hen, feed their young entirely upon the 

 larva of insects. The finches and sparrows are therefore 

 insectivorous, with but a few exceptions, the first two or 

 three months of their existence.. They do not consume 

 grain or seeds until they are able to provide for themselves. 

 The old birds supply their young with larva, when this 

 kind of food is abundant, and when the tender sta:te of 

 their digestive organs requires the use of soft food. Ac- 

 cording to Mr. Augustus Fowler, who is good authority 

 for any original observations, the American Goldfinch 

 waits, before it builds a nest, until it is so late that the 

 young, when they appear, may be fed with the milky 

 grains and seeds of plants. It should be added that 

 doves and pigeons soften the grain in their own crop be- 

 fore they give it to their young. 



