dia K. inachis, and in the larger Malay islands K. paralekta, are
very common. They are rather large and showy butterflies, orange and
bluish on the upper side, with a very rapid flight, and frequenting dry
forests. Their habit is to settle always where there is some dead or
decaying foliage, and the shape and colour of the wings (on the under
surface), together with the attitude of the insect, is such as to
produce an absolutely perfect imitation of a dead leaf. This is effected
by the butterfly always settling on a twig, with the short tail of the
hind wings just touching it and forming the leaf-stalk. From this a dark
curved line runs across to the elongated tip of the upper wings,
imitating the midrib, on both sides of which are oblique lines, formed
partly by the nervures and partly by markings, which give the effect of
the usual veining of a leaf. The head and antennae fit exactly between
the closed upper wings so as not to interfere with the outline, which
has just that amount of irregular curvature that is seen in dry and
withered leaves. The colour is very remarkable for its extreme amount of
variability, from deep reddish-brown to olive or pale yellow, hardly two
specimens being exactly alike, but all coming within the range of colour
of leaves in various stages of decay. Still more curious is the fact
that the paler wings, which imitate leaves most decayed, are usually
covered with small black dots, often gathered into circular groups, and
so exactly resembling the minute fungi on decaying leaves that it is
hard at first to believe that the insects themselves are not attacked by
some such fungus. The concealment produced by this wonderful imitation
is most complete, and in Sumatra I have often seen one enter a bush and
then disappear like magic. Once I was so fortunate as to see the exact
spot on which the insect settled; but even then I lost sight of it for
some time, and only after a persistent search discovered that it was
close before my eyes.[75] Here we have a kind of imitation, which is
very common in a less developed form, carried to extreme perfection,
with the result that the species is very abundant over a considerable
area of country.

_Protective Resemblance among Marine Animals._

Among marine animals this form of protection is very common. Professor
Moseley tells us that all the inhabitants of the Gulf-weed are most
remarkably coloured, for purposes of protection and concealment, exactly
lik