explanation I gave at the time. The male of Papilio Memnon is a large
black butterfly with the nervures towards the margins of the wings
bordered with bluish gray dots. It is a forest insect, and the very
dark colour renders it conspicuous; but it is a strong flier, and thus
survives. To the female, however, this conspicuous mass of colour
would be dangerous, owing to her slower flight, and the necessity for
continually resting while depositing her eggs on the leaves of the
food-plant of the larva. She has accordingly acquired lighter and more
varied tints. The marginal gray-dotted stripes of the male have become
of a brownish ash and much wider on the fore wings, while the margin
of the hind wings is yellowish, with a more defined spot near the
anal angle. This is the form most nearly like the male, but it is
comparatively rare, the more common being much lighter in colour, the
bluish gray of the hind wings being often entirely replaced by a broad
band of yellowish white. The anal angle is orange-yellow, and there is
a bright red spot at the base of the fore wings. Between these two
extremes there is every possible variation. Now, it is quite certain
that this varying mixture of brown, black, white, yellow, and red is far
less conspicuous amid the ever-changing hues of the forest with their
glints of sunshine everywhere penetrating so as to form strong contrasts
and patches of light and shade. Hence ALL the females--one at one time
and one at another--get SOME protection, and that is sufficient to
enable them to live long enough to lay their eggs, when their work is
finished. Still, under bad conditions they only just managed to
survive, and as the colouring of some of these varying females very
much resembled that of the protected butterflies of the P. coon
group (perhaps at a time when the tails of the latter were not fully
developed) any rudiments of a prolongation of the wing into a tail added
to the protective resemblance, and was therefore preserved. The woodcuts
of some of these forms in my "Malay Archipelago" (i., page 200) will
enable those who have this book at hand better to understand the
foregoing explanation."), and should be grateful for an explanation, for
I want fully to understand you. How can one female form be selected and
the intermediate forms die out, without also the other extreme form also
dying out from not having the advantages of the first selected form?
for, as I understand, both female form