Mr. Keartons Idea. 153 



ducing the size of their eggs slowly and yet them- 

 selves brooding them till they had brought them to 

 a certain point, and then began, "through the selec- 

 tion of self-originating tricks," their process of para- 

 sitism. This would, perhaps, be the most daring 

 instance under evolutionary law of a clear and con- 

 scious preparation, in view of succeeding at last in a 

 practical way, " through the selection of self-originat- 

 ing tricks " — the birds of the early time far-feeling 

 forward to our later time, like prophets of infinitely 

 more than Mosaic forecast. 



It must have been in one of either of these ways 

 the change was effected, and we should be obliged to 

 Mr. Grant Allen, as the most popular and facile of 

 evolutionist expositors and illustrators, to tell us 

 which it was. 



Mr. Kearton writes : 



" It is certain that the cuckoo lays more than one 

 egg ; but, although naturahsts of good repute have 

 mentioned the number as five, and others have been 

 of opinion that even a larger number may be laid, 

 there is, so far as I know, no reliable evidence to 

 support either supposition. 



" I have never noticed that young cuckoos exceeded 

 in numbers the old ones, in a given district where I 

 was out of doors all day long, every day in the year, 

 and many years together in unbroken succession. 

 But, of course, the nuinber hatched could never repre- 

 sent the munber laid, althoufrh the place to which I 

 refer was singularly free from vermin and collectors."-'' 



If so, to what could the great disparity between 

 eggs laid and eggs hatched be due ? Special causes 



* British Birds' Nests, p. 42. 



