CHAPTER XI 
CONDITIONS GOVERNING THE LAYING OF CUCKOOS 
IN GENERAL 
More than sufficient evidence has been produced 
in support of my theory, that a dominant hen 
Cuckoo, by a process of watching and searching, 
discovers some days in advance the nests of those 
dupes in which she intends subsequently to deposit 
an egg. I contend that the watching of her dupes 
engaged in building stimulates her own reproductive 
organs and the resulting egg is ready for extrusion 
about five or six days afterwards. It follows that 
within reasonable limits the number of eggs she 
lays is regulated by the number of suitable nests 
discovered ; though of course in cases of emergency 
a Cuckoo will sometimes make use of what are to 
her unnatural fosterers. 
Ever since I began to study the subject, I have 
argued that the number of eggs that a Cuckoo 
might lay in a season probably depended in great 
measure upon the number of regularly available 
nests of the particular species which nature inclined 
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