" Inconveniently Long." loi 



XI. 



Mr. Darwin found the cuckoo one of the most diffi- 

 cult creatures he had to tackle — to explain and to 

 reconcile the phenomena it presents with his theories 

 of evolution and natural selection. In fact, the great 

 master there just wrote a little nonsense, and, though 



" a little nonsense now and then is relished by 

 the wisest men," 



we could not rehsh it from Darwin, who had as little 

 of fun about him as he had, as he himself confessed, 

 of poetry. He wrote, in the remarkable 8th chapter 

 of the Origin of Species, 6th edition, as follows : 



" It is now commonly admitted that the more im- 

 mediate cause of the cuckoo's instinct is that she lays 

 her eggs, not daily, but at intervals of two or three 

 days, so that if she were to make her own nest, and 

 sit upon her own eggs, those first laid would have to 

 be left for some time unincubated, or there would be 

 eggs and young birds of different ages in the same nest. 

 If this were the case, the process of laying and hatch- 

 ing might be inconveniently long, more especially as 

 she has to migrate at a very early period, and the first 

 hatched young would probably have to be fed by the 

 male alone." (Italics in the two places are mine.) 



In answer to this proposition it has been very well 

 written : 



" Might it not just as reasonably be said that the 

 parasitic instinct is the more immediate and final 

 cause of her laying her eggs at long intervals ? " 



And Mr. Darwin thus proceeds : 



