insects. Hence, we may conclude that, if insects had not been
developed on the face of the earth, our plants would not have been
decked with beautiful flowers, but would have produced only such poor
flowers as we see on our fir, oak, nut and ash trees, on grasses,
spinach, docks and nettles, which are all fertilised through the agency
of the wind. A similar line of argument holds good with fruits; that
a ripe strawberry or cherry is as pleasing to the eye as to the
palate--that the gaily-coloured fruit of the spindle-wood tree and the
scarlet berries of the holly are beautiful objects--will be admitted by
everyone. But this beauty serves merely as a guide to birds and
beasts, in order that the fruit may be devoured and the matured seeds
disseminated. I infer that this is the case from having as yet found
no exception to the rule that seeds are always thus disseminated when
embedded within a fruit of any kind (that is within a fleshy or
pulpy envelope), if it be coloured of any brilliant tint, or rendered
conspicuous by being white or black.

On the other hand, I willingly admit that a great number of male
animals, as all our most gorgeous birds, some fishes, reptiles, and
mammals, and a host of magnificently coloured butterflies, have been
rendered beautiful for beauty's sake. But this has been effected through
sexual selection, that is, by the more beautiful males having been
continually preferred by the females, and not for the delight of man. So
it is with the music of birds. We may infer from all this that a nearly
similar taste for beautiful colours and for musical sounds runs through
a large part of the animal kingdom. When the female is as beautifully
coloured as the male, which is not rarely the case with birds and
butterflies, the cause apparently lies in the colours acquired through
sexual selection having been transmitted to both sexes, instead of to
the males alone. How the sense of beauty in its simplest form--that is,
the reception of a peculiar kind of pleasure from certain colours, forms
and sounds--was first developed in the mind of man and of the lower
animals, is a very obscure subject. The same sort of difficulty is
presented if we enquire how it is that certain flavours and odours give
pleasure, and others displeasure. Habit in all these cases appears
to have come to a certain extent into play; but there must be some
fundamental cause in the constitution of the nervous system in each
species.

Na