h in nitrobenzine,
must assuredly have complacent gullets and adaptable stomachs. Yet these
robust eaters die of hunger or poison for no greater cause than a drop
of syrup, the lightest diet imaginable, adapted to the weakness of
extreme youth, and a delicacy to the adult! What a gulf of obscurity in
the stomach of a miserable worm!

These gastronomic experiments called for a counter-proof. The
carnivorous grub is killed by honey. Is the honey-fed grub, inversely,
killed by carnivorous diet? Here, again, we must make certain
exceptions, observe a certain choice, as in the previous experiments. It
would obviously be courting a flat refusal to offer a heap of young
crickets to the larvae of the Anthophorus and the Osmia, for example; the
honey-fed grub would not bite such food. It would be absolutely useless
to make such an experiment. We must find the equivalent of the bee
smeared with honey; that is, we must offer the larva its ordinary food
with a mixture of animal matter added. I shall experiment with albumen,
as provided by the egg of the hen; albumen being an isomer of fibrine,
which is the principal element of all flesh diet.

_Osmia tricornis_ will lend itself to my experiment better than any
other insect on account of its dry honey, or bee-bread, which is largely
formed of flowery pollen. I knead it with the albumen, graduating the
dose of the latter so that its weight largely exceeds that of the
bee-bread. Thus I obtain pastes of various degrees of consistency, but
all firm enough to support the larva without danger of immersion. With
too fluid a mixture there would be a danger of death by drowning.
Finally, on each cake of albuminous paste I install a larva of medium
growth.

This diet is not distasteful; far from it. The grubs attack it without
hesitation and devour it with every appearance of a normal appetite.
Matters could not go better if the food had not been modified according
to my recipes. All is eaten; even the portions which I feared contained
an excessive proportion of albumen. Moreover--a matter of still greater
importance--the larvae of the Osmia fed in this manner attain their
normal growth and spin their cocoons, from which adults issue in the
following year. Despite the albuminous diet the cycle of evolution
completes itself without mishap.

What are we to conclude from all this? I confess I am embarrassed. _Omne
vivum ex ovo_, says the physiologist. All animals are carnivorous in
their fi