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travagant calculation, since he undoubtedly employs nearly 

 twelve hours of the twenty-four in searching for food, and we 

 may suppose a twelfth part of this time devoted to this de- 

 scription of foraging. At the rate of seventeen per minute, 

 each bird would destroy a little more than one thousand cater- 

 pillars in the course of each day. We may rationally conclude 

 from this calculation, even if we reduce it to one half the 

 amount, this species of birds must destroy an immense quan- 

 tity of these vermin during the three or four weeks of the 

 caterpillar season, and that they must serve as a most important 

 check upon their multiplication. 



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

 observer, having discovered a nest of five young jays, remarked 

 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 makes a cal- 

 culation founded on the supposition that they would require, 

 of large and small, about twenty each for their daily supply. 

 At this rate, the five birds together would consume 100. Al- 

 lowing that each of the parents required 50, the family would 

 consume 200 every day ; and the whole would amount in three 

 months, or one season, to 20,000. The writer, I would re- 

 mark, commits an error in supposing that the old birds con- 

 sume more than their young ; whereas they feed upon com- 

 paratively few soft insects, or grubs, giving these to their 

 young, while they make their own meals upon the hard and 

 coriaceous insects. The old bird consumes, for example, the 

 beetle, while he feeds his young upon its larva. 



In obedience to a similar instinct, many of the granivorous 

 birds, as the Sparrows and Finches, while they live chiefly 

 upon seeds, feed their young entirely upon the larva of insects. 

 Almost every Finch and Sparrow is, therefore, insectivorous 

 for the first few weeks of its existence, not consuming seeds or 

 grain, until it has learned to provide for its own subsistence. 

 The old birds supply their young with larva, when this kind 

 of food is abundant, and when the tender state of their digestive 

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