latter case, and in many others, is apparently wholly due to symmetry of
growth. Flowers rank among the most beautiful productions of nature; but
they have been rendered conspicuous in contrast with the green leaves, and
in consequence at the same time beautiful, so that they may be easily
observed by insects. I have come to this conclusion from finding it an
invariable rule that when a flower is fertilised by the wind it never has a
gaily-coloured corolla. Several plants habitually produce two kinds of
flowers; one kind open and coloured so as to attract insects; the other
closed, not coloured, destitute of nectar, and never visited by 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