Colours of Eggs 
‘©5. Many birds lay eggs which exhibit very 
great variations. 
“6, Some birds lay eggs of different types, 
and these sometimes differ from one another so 
greatly that it is difficult to believe that they 
could have been laid by the same species.” ! 
7. It not infrequently happens that one species 
lays in the disused nest of another, and the eggs 
of the latter are often very different in colouring 
from those of the former. 
We have up to the present considered the theory 
of general cryptic colouration, which declares that 
the majority of creatures are so coloured as to be 
inconspicuous. We have still to deal with the 
hypothesis of special cryptic colouring. 
Certain animals look, when resting, very like 
an inanimate object, such as a dead leaf or a 
twig. This resemblance is said to be the result 
of natural selection, since it enables its possessors 
to escape destruction; they are seen, but mis- 
taken for something else. 
The classical examples of this kind of protec- 
tive colouring are furnished by the Kadimas or 
leaf-butterflies, which display an extraordinary 
resemblance to dead leaves. 
Other examples are the stick-insects and the 
lappet moth, which looks like a bunch of dry 
leaves. It is needless to multiply instances. 
1 Journal of the Bombay Natural History Society, Vol. xv. 
1903-4), P. 454. 
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