aper read before the Rugby School Natural History Society, gives the
following original observation:--"I myself have more than once mistaken
Cilix compressa, a little white and grey moth, for a piece of bird's
dung dropped upon a leaf, and _vice versa_ the dung for the moth.
Bryophila Glandifera and Perla are the very image of the mortar walls on
which they rest; and only this summer, in Switzerland, I amused myself
for some time in watching a moth, probably Larentia tripunctaria,
fluttering about quite close to me, and then alighting on a wall of the
stone of the district which it so exactly matched as to be quite
invisible a couple of yards off." There are probably hosts of these
resemblances which have not been observed, owing to the difficulty of
finding many of the species in their stations of natural repose.
Caterpillars are also similarly protected. Many exactly resemble in tint
the leaves they feed upon; others are like little brown twigs, and many
are so strangely marked or humped, that when motionless they can hardly
be taken to be living creatures at all. Mr. Andrew Murray has remarked
how closely the larva of the peacock moth (Saturnia pavonia-minor)
harmonizes in its ground colour with that of the young buds of heather
on which it feeds, and that the pink spots with which it is decorated
correspond with the flowers and flower-buds of the same plant.

The whole order of Orthoptera, grasshoppers, locusts, crickets, &c., are
protected by their colours harmonizing with that of the vegetation or
the soil on which they live, and in no other group have we such striking
examples of special resemblance. Most of the tropical Mantidae and
Locustidae are of the exact tint of the leaves on which they habitually
repose, and many of them in addition have the veinings of their wings
modified so as exactly to imitate that of a leaf. This is carried to the
furthest possible extent in the wonderful genus, Phyllium, the "walking
leaf," in which not only are the wings perfect imitations of leaves in
every detail, but the thorax and legs are flat, dilated, and leaf-like;
so that when tho living insect is resting among the foliage on which it
feeds, the closest observation is often unable to distinguish between
the animal and the vegetable.

The whole family of the Phasmidae, or spectres, to which this insect
belongs, is more or less imitative, and a great number of the species
are called "walking-stick insects," from their singu