which it was spun, I never have seen a cocoon with shred, filament,
or particle of anything used in its composition that was not drawn
from the spinning tube or internal organism of the caterpillar,
with the possible exception of a few hairs from the tubercles. I
have been told by other workers that they have had captive caterpillars
use earth and excrement in their cocoons.

This same work, in an article on protective colouration, lays
emphasis on the statement that among pupa cases artificially
fastened to different objects out of doors, "the elimination was
ninety-two per cent on fences where pupae were conspicuous, as
against fifty-two per cent among nettles, where they were inconspicuous."
This statement is elaborated and commented upon as making a strong
point for colourative protection through inconspicuousness.

Personally, I think the nettles did the work, regardless of colour.
I have learned to much experience afield that a patch of nettles or
thistles afford splendid protection to any form of life that can
survive them. I have seen insects and nesting birds find a safety
in their shelter, unknown to their kind that home elsewhere. The
test is not fair enough to be worth consideration. If these same
pupae had been as conspicuously placed as on the fence, on any
EDIBLE GROWTH, in the same location as the fence, and then left to
the mercy of playing children, grazing stock, field mice, snakes,
bats, birds, insects and parasites, the story of what happened to
them would have been different. I doubt very seriously if it
would have proved the point those lepidopterists started out to
make in these conditions, which are the only fair ones under which
such an experiment could be made.