356 THE ZOOLOGIST. 



to prove that usually one egg is abstracted by the Cuckoo when it 

 iDtroduces its egg into the nest of its dupe; in some instances the 

 Cuckoo has been seen with the egg in its beak. Indeed, the proof of 

 the removal of at least one egg of the dupe by the Cuckoo, when it 

 foists its egg on the nest of its victim, is so great as to practically 

 amount to a demonstration. The next question Mr. Steele Elliott 

 raises is, What becomes of the egg or eggs taken by the Cuckoo out 

 of the nest of its victim? I have no hesitation in affirming my 

 belief that they are eaten by the Cuckoo, although I am aware that 

 this is stoutly denied even by at least some naturalists of high 

 repute. How are we to account otherwise for the number of egg- 

 shells found in the neighbourhood of nests, which have lost one or 

 more eggs through abstraction by Cuckoos ? Moreover, we have it 

 on the authority of Mr. Nelson recorded in the ' Field ' of January 28th, 

 1882, that on skinning a Cuckoo he found its crop full of eggs ; and 

 in writing of the birds of the Norfolk Broads, Mr. Emerson says he 

 found in the crops of Cuckoos what appeared to be yolk of eggs (see 

 Mr. Gurney on the Economy of the Cuckoo). A good many other 

 instances might be given in confirmation of this egg-eating pro- 

 pensity on the part of the Cuckoos. I should not, however, like 

 to assert that its common habit is to eat eggs other than from those 

 nests which it victimizes. A good many other points in the life- 

 history of the Cuckoo require elucidation, amongst which might be 

 mentioned the following: — 



1. Is the well-known double note peculiar to the male? 



2. How many eggs are usually laid in a season ? 



3. What interval elapses between the laying of each egg, and is 

 this regular or irregular ? 



4. Does the Cuckoo confine its attention chiefly to one species in 

 any one district ? 



5. After the laying of its eggs in the nest of its dupe, does the 

 Cuckoo ever take any interest in its future progeny ? 



6. Has the Cuckoo ever been known to incubate its own egg? 



7. Does the Cuckoo lay in the nests of a greater number of 

 species than it formerly did ? 



8. Does the Cuckoo sometimes remove the nestlings of birds ? 



9. Is the Cuckoo polyandrous to the extent that it is usually 

 asserted to be ? 



I should be very glad to receive information from any of your 

 readers as to the number of species of birds the Cuckoo victimizes in 

 any given district, or even the dominant species. The life-history of 

 the Cuckoo is an inexhaustible subject, as well as a very fascinating 



