8 Life History of Common Cuckoo. 



small birds are insect-eaters, and at certain seasons 

 of the year they feed on nothing else." * 



If it should be found that there is anything in the 

 suggestion above, it presents quite a new phase of 

 adaptation due to special circumstances. 



Mr. Westley T. Page, F.Z.S., whose experience is 

 very large, writes generally thus : — " Though wax- 

 bills and finches will do well for a long time on seed 

 alone, they are the better in condition, and more bril- 

 liant in plumage for the soft food and an occasional 

 insect." t 



Waterton indeed seriously raises the question 

 whether severity of climate and the food question 

 have anything to do with migration, since he finds 

 that, like most of the migrants, the wren, the hedge- 

 sparrow and the robin are insectivorous birds, and yet 

 can manage not only to subsist through the English 

 winter but to increase their numbers. 



Of all birds the stomach and digestive organs of the 

 cuckoo would seem to render it most unsuited for seed- 

 eating ; yet we are quite aware that White, of Sel- 

 borne, in his dissections, found among worms, flies 

 and caterpillars, many seeds in the stomach of the 

 cuckoo — seeds which, on our theory, would be taken 

 so far medicinally, perhaps, more than aught else, as 

 dogs and many carnivorous creatures eat grass, etc., 

 with this view. But the wonderful adaptations of 

 nature in providing exceptional cases to all rules is 

 what to us forms the special attraction of natural 

 history study and observation. 



Let us end this section as we almost began it, by 



* H. Nehrling, i, p. xxviii. 



+ The Feathered World, 14th July, 1899, p. 42. 



