ecause white is the most conspicuous
of all colours for nocturnal insects, and had they not some other
protection would certainly be very injurious to them.

_Lepidoptera mimicking other Insects._

In the preceding cases we have found Lepidoptera imitating other species
of the same order, and such species only as we have good reason to
believe were free from the attacks of many insectivorous creatures; but
there are other instances in which they altogether lose the external
appearance of the order to which they belong, and take on the dress of
bees or wasps--insects which have an undeniable protection in their
stings. The Sesiidae and AEgeriidae, two families of day-flying moths, are
particularly remarkable in this respect, and a mere inspection of the
names given to the various species shows how the resemblance has struck
everyone. We have apiformis, vespiforme, ichneumoniforme, scoliaeforme,
sphegiforme (bee-like, wasp-like, ichneumon-like, &c.) and many others,
all indicating a resemblance to stinging Hymenoptera. In Britain we may
particularly notice Sesia bombiliformis, which very closely resembles
the male of the large and common humble bee, Bombus hortorum; Sphecia
craboniforme, which is coloured like a hornet, and is (on the authority
of Mr. Jenner Weir) much more like it when alive than when in the
cabinet, from the way in which it carries its wings; and the currant
clear-wing, Trochilium tipuliforme, which resembles a small black wasp
(Odynerus sinuatus) very abundant in gardens at the same season. It has
been so much the practice to look upon these resemblances as mere
curious analogies playing no part in the economy of nature, that we have
scarcely any observations of the habits and appearance when alive of the
hundreds of species of these groups in various parts of the world, or
how far they are accompanied by Hymenoptera, which they specifically
resemble. There are many species in India (like those figured by
Professor Westwood in his "Oriental Entomology") which have the hind
legs very broad and densely hairy, so as exactly to imitate the
brush-legged bees (Scopulipedes) which abound in the same country. In
this case we have more than mere resemblance of colour, for that which
is an important functional structure in the one group is imitated in
another whose habits render it perfectly useless.

_Mimicry among Beetles._

It may fairly be expected that if these imitations of one creature by
another