86 



The Naturalist. 



insectivorous during the breeding season, and according to my 

 experience, are as common as tlie starling : — 



Reckoning these at the same rate as starlings, gives us 30,000,000. 

 Now say that there are only half as many of each of the following 

 birds : — 



The latter 17 species would give us 17,000,000 individuals, which 

 added to the previous numbers gives us 47,000,000. There are also 

 many insectivorous birds which are fairly common, such as the wood 

 wren, chiff-chaff, lesser white-throat, stonechat, blackcap, garden 

 warbler, &c., &c., which I have not enumerated, but say in round 

 numbers that there are 50,000,000 insectivorous birds in this 

 country during May, June, and July. This will be 25,000,000 pairs ; 

 reckon each pair to destroy as many caterpillars as the blue tits, 600 

 a-day, during say one month, 30 x 600 = 18,000. Now, multiply 25 

 millions by 18,000 and we get the amazing number of 450,000,000,000, 

 the number of caterpillars destroyed by small birds during one month 

 in the year. Has any reader of the Naturalist any idea what these 

 numbers represent ? Let us try and form some idea. Say a pint 

 measure would hold 500 caterpillars, that would give us 900,000,000 

 pints, and about the same number of lbs. If we now reduce these lbs. 

 to tons, we find that we arrive at the enormous sum total of 401,785 

 tons. Let us simplify it still more, and say that they would fill over 

 200 railway trains, each train having 20 waggons, holding 10 tons ! ! 

 These figures are perfectly astounding, and I can scarcely credit my 

 own calculations. Remember that these calculations are but for one 

 month out of twelve ; but if we allow the same numbers for the whole 

 of the year, it is enough to turn the stomach of any thinking 



1. Hedge sparrow. 



2. Robin. 



3. Willow wren. 



4. Pied wagtail. 



5. Tree pipit. 



6. Meadow pipit. 



7. Skylark. 



8. YeUow hammer. 



9. House sparrow. 



10. Linnet. 



11. Swallow. 



12. Martin.- 



13. Sand martin. 



14. Swift. 



1. Whinchat. 



2. Wheatear. 



3. Sedge warbler. 



4. Black cap. 



5. White throat. 



6. Blue tit. 



7. Ray's wagtail. 



8. Common bunting. 



10. Greenfinch. 



11. Twite. - 



12. Wood pecker. 



13. Wren. 



14. Cuckoo. 



15. Nightjar. 



16. Partridge. 



17. Quail. 



9. Chaffinch. 



