discover that it was close before my eyes, but that in its position of
repose it so closely resembled a dead leaf attached to a twig as almost
certainly to deceive the eye even when gazing full upon it. I captured
several specimens on the wing, and was able fully to understand the way
in which this wonderful resemblance is produced.
The end of the upper wings terminates in a fine point, just as the
leaves of many tropical shrubs and trees are pointed, while the lower
wings are somewhat more obtuse, and are lengthened out into a short
thick tail. Between these two points there runs a dark curved line
exactly representing the midrib of a leaf, and from this radiate on each
side a few oblique marks which well imitate the lateral veins. These
marks are more clearly seen on the outer portion of the base of the
wings, and on the innerside towards the middle and apex, and they are
produced by striae and markings which are very common in allied species,
but which are here modified and strengthened so as to imitate more
exactly the venation of a leaf. The tint of the undersurface varies
much, but it is always some ashy brown or reddish colour, which matches
with those of dead leaves. The habit of the species is always to rest on
a twig and among dead or dry leaves, and in this position with the
wings closely pressed together, their outline is exactly that of a
moderately-sized leaf, slightly curved or shrivelled. The tail of the
hind wings forms a perfect stalk, and touches the stick while the insect
is supported by the middle pair of legs, which are not noticed among the
twigs and fibres that surround it. The head and antennae are drawn back
between the wings so as to be quite concealed, and there is a little
notch hollowed out at the very base of the wings, which allows the
head to be retracted sufficiently. All these varied details combine to
produce a disguise that is so complete and marvellous as to astonish
everyone who observes it; and the habits of the insects are such as to
utilize all these peculiarities, and render them available in such a
manner as to remove all doubt of the purpose of this singular case of
mimicry, which is undoubtedly a protection to the insect.
Its strong and swift flight is sufficient to save it from its enemies
when on the wing, but if it were equally conspicuous when at rest
it could not long escape extinction, owing to the attacks of the
insectivorous birds and reptiles that abound in the tropical forests. A
very closely allied species, Kallima inachis, inhabits India, where
it is very common, and specimens are sent in every collection from the
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