Dr. A. E. Brehm's 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 foundling, and in 

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



