INSEINGTS OF MOLOTHRUS 
of the genus. Moreover, just as a criminal will practise 
upon his own class, just as there is no honour among 
thieves, but thief will rob thief, so one species of Molo- 
thrus, viz., M. rufo-axillaris, will lay its eggs in the 
nest of M. badius, a form which is not itself parasitic. 
Nature has aided and abetted this iniquitous mode of 
life in many and varied ways. These have been care- 
fully studied upon the spot by Mr. W. H. Hudson, from 
whose account of the same in the Proceedings of the 
Zoological Society we shall quote. The cow bird appears 
to have adopted the habits of the cuckoo at a later 
period in the history of its race than that bird, for it 
often makes rather serious mistakes. For example, 
Molothrus has been known to drop its eggs on the 
ground, omitting to remove them carefully and subse- 
quently in its bill to some adjacent nest, as does the 
cuckoo. Its instincts are as yet so primitive and 
uncultured that the bird will lay its eggs in an old 
and deserted nest, or fail to hit the right time for egg 
laying, when its young, being born too late, perish of 
neglect at the hands of their foster parents. This latter 
error, however, appears to be remedied by the fact 
that the young are hatched especially early, and are 
also peculiarly strong. Molothrus, when it does success- 
fully lay its eggs in a stranger’s nest, is apt to make 
assurance doubly sure by pecking at and destroying 
the legitimate eggy occupants of the nest; in doing 
this, it will occasionally peck at its own eggs, or rather 
those of another Molothrus who has been beforehand 
with it. This danger to future generations of Molothri 
is to some extent evaded by the very hard nature of the 
shell, which resists pecking more efficiently than do the 
eggs of the unconsulted hosts. The cuckoo’s eggs, as a 
matter of quite common knowledge, are varied in hue, 
so as to give them a better chance of escaping unnoticed 
in the nests of their unwilling hosts. Precisely the 
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