d for a counterexperiment. The
carnivorous larva is killed by honey. Conversely, is the mellivorous
larva killed by animal food? Reservations are needful here, as in the
previous tests. We should be courting a flat refusal if we offered
a pinch of Locusts to the larvae of the Anthophora or the Osmia, for
instance. (For both these Wild Bees cf. "Bramble-bees and Others":
passim.--Translator's Note.) The honey-fed insect would not bite
into it. There would be no use whatever in trying. We must find the
equivalent of the jam-sandwich aforesaid; in other words, we must give
the larva its natural fare with a mixture of animal food. The addition
made by my artifices shall be albumen, as found in the egg of the Hen,
albumen the isomer of fibrin, which is the essential factor in any form
of prey.
On the other hand, the Three-horned Osmia lends herself most admirably
to my plans, because of her dry honey, consisting for the greater part
of floury pollen. I therefore knead this honey with albumen, graduating
the dose until its weight largely exceeds that of the flour. In this way
I obtain pastes of different degrees of consistency, but all firm enough
to bear the larva without danger of immersion. With too fluid a
mixture there would be a risk of death by drowning. Lastly I install a
moderately-developed larva on each of my albuminous cakes.
The dish of my inventing does not incite dislike: far from it. The grubs
attack it without hesitation and consume it with every appearance of
the usual appetite. Things could not go better if the food had not been
altered by my culinary recipes. Everything goes down, including the
morsels in which I feared that I had overdone the addition of albumen.
And--an even more important point--the Osmia-larvae fed in this manner
attain their normal dimensions and spin their cocoons, from which adult
insects issue in the following year. Notwithstanding the albuminous
regimen, the cycle of the evolution is achieved without impediment.
What are we to conclude from all this? I feel greatly embarrassed. Omne
vivum ex ovo, the physiologists tell us. Every animal is carnivorous, in
its first beginnings: it is formed and nourished at the cost of its egg,
in which albumen predominates. The highest, the mammal, adheres to this
diet for a long time: it has its mother's milk, rich in casein, another
isomer of albumen. The gramnivorous nestling is first fed on grubs,
which are better adapted to the niceties o
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