Life-history of the Cuckoo. 125 
Finches and Buntings: these exceptions being doubtless in cases 
only where the Cuckoo was deprived, by some accident, of the nest 
she had selected for her egg, and which when ready to be laid, she 
was obliged to consign to the care of the best nurse she could find 
at short notice. To this seeming inconsistency on the part of the 
parent bird, I may however add, that grain-eating species have 
been known to bring up young Cuckoos; and the explanation is, 
that even the hard-billed birds are accustomed to feed their young, 
at any rate at first, with insects. 
From the thirty-seven species alluded to above, which have been 
ascertained to act as foster parents of the young Cuckoo, Dr. 
Baldamus enumerates no less than twenty-eight, to whose several 
eggs he affirms the Cuckoo will assimilate her egg in colouring ; 
-and this he then proceeds to prove from the specimens lying before 
him, and which (as I before remarked) are all carefully authenti- 
cated, in regard to the nests from which they were taken: all these 
specimens he examines singly, and describes their colouring, as 
nearly all partaking, in a greater or less degree, of the character, 
ground colour, and markings of the eggs of the species in whose 
nests they were severally laid: while some are so extremely similar 
that but for the grain! or texture of the shell and certain charac- 
teristic specks, it would be difficult to distinguish them apart. The 
exceptions to this general rule, are those laid in the nests of corn- 
eating species, and our author adds, that it would be extraordinary 
indeed, if the Cuckoo’s eggs should resemble the eggs of these 
exceptional and never intended foster parents. 
“The fact then” (says Dr. Baldamus) “is quite established and 
beyond all doubt, that there are Cuckoo’s eggs, which both in 
colour and in marking, are very like the eggs of those species in 
whose nests they are generally laid:” and then he proceeds to 
argue that Nature, who never trifles, nor acts without purpose, has 
plainly given the parent Cuckoo this faculty, in order to facilitate 
16¢ Das Korn:” the German word exactly answering to our English idiom 
‘Corain.” The grain or texture of the shell is too often overlooked by Oologist’s, 
but amongst the very similar eggs of some species, as more particularly among 
the Duck tribe, this is one very important means of identification, more es- 
_ pecially when the egg is placed under a low magnifying power. 
