r its elegance, with its
spiral mouldings, its thimble-pits and its hop-scales? A few little
accidental facts put me on the right track. To begin with, I acquire
the certainty that the egg does not descend from the ovaries as I find
it on the ground. Its ornamentation, incompatible with a gentle
gliding movement, had already told me as much; I now have a clear
proof.

Mingled with the normal eggs of both the Golden Cryptocephalus and the
Long-legged Clythra, I find others which differ in no respect from the
usual run of insects' eggs. The eggs are perfectly smooth, with a
soft, pale-yellow shell. As the cage contains no other insects than
the Clythra under consideration or the Cryptocephalus, I cannot be
mistaken as to the origin of my finds.

Moreover, if any doubts remained, they would be dispelled by the
following evidence: in addition to the bare, yellow eggs there are
some whose base is set in a tiny brown, pitted cup, obviously the work
of either the Two-spotted Cryptocephalus or the Long-legged Clythra,
according to the cage, but unfinished work, which half-clothed the
egg, as it left the ovaries, and then, when the dress-material ran
short, or something went wrong with the machinery, allowed it to cross
the outer threshold in the likeness of an acorn fixed in its cup.

Nothing could be prettier than this yellow egg, standing in its
artistic egg-cup. Nor could anything tell us more conclusively where
the jewel is manufactured. It is in the cloaca, the chamber common to
the oviduct and the intestine, that the bird wraps its egg in a
calcareous shell, often decorating it with magnificent hues:
olive-green for the Nightingale, sky-blue for the Wheatear, soft pink
for the Icterine Warbler. It is in the cloaca also that the Clythra
and the Cryptocephalus produce the elegant armour of their eggs.

It remains to decide upon the material employed. From its horny
appearance there is reason to believe that the little barrel of the
Taxicorn Clythra and the scales of the Four-spotted Clythra are the
products of a special secretion; and, now that it is too late, I much
regret that I neglected to look for the apparatus yielding this
secretion in the neighbourhood of the cloaca. As for the thing so
prettily wrought by the Long-legged Clythra and the Cryptocephali, let
us admit without false shame that it is made of faecal matter.

The proof is furnished by certain specimens, by no means rare in the
Golden Cryptocephalus,