Dr. A. E. Brehms Anecdote. 25 



Summer Migrants, of reminding him that the same 

 observations had already been recorded by Jenner, 

 Montagu, Blackwall, Durham Weir, and Adolf 

 Miiller. But Mr. Gould's, from the extracts above, 

 was a re-conversion. In 1837, he, like yet bigger 

 men, implicitly followed Jenner ; in 1873 alongside a 

 drawing of the young cuckoo in the act of ejecting the 

 true young, he actually set down a caveat against 

 this charge and explained the facts differently, and 

 then, later, was reconverted to his opinion of 1837. 

 His case here was an exact illustration of Tennyson's 

 words : — 



" It is not true that second thoughts are best, 

 But first and third, which are a riper first." 



The necessity for complete success in extermina- 

 tion of foster-birds' progeny on the cuckoo's plan 

 may be found in this that when any of the true young 

 are left, the proper instinct of the foster-parents will 

 more or less assert itself. This has confirmation in 

 the following anecdote from Dr. A. E. Brehm, told 

 through the Rev. A. C. Smith : 



" In June, 1812, says my father, a wren's nest 

 was found on the manor of Frohlichen-wiederkunft, 

 which contained two young wrens and a cuckoo — 

 quite an exceptional case ; the dome of the nest had 

 preserved the young wrens from being ejected by the 

 cuckoo. A friend of mine took the cuckoo when it 

 was almost ready to fly and, as is often done by bird 

 fanciers, placed it in a cage, intending to bring it to 

 me as soon as it was fledged. The foster-parents in 

 this case, however, abandoned the foundhng, and in 

 two days it was found starved to death ; the wrens, 



