To interrupt the larva with the object of smearing the interior of its prey with honey is doubly objectionable; I might extinguish the lingering vitality which keeps putrefaction at bay in the victim, and I might confuse the delicate art of the larva, which might not be able to recover the lode at which it was working or to distinguish between those parts which are lawfully and properly eaten and those which must not be consumed until a later period.  As I have shown in a previous volume, the grub of the Scolia has taught me much in this respect.  The only larvae acceptable for this experiment are those which are fed on a number of small insects, which are attacked without any special art, dismembered at random, and quickly consumed.  Among such larvae I have experimented with those provided by chance—­those of various Bembeces, fed on Diptera; those of the Palaris, whose diet consists of a large variety of Hymenoptera; those of the Tachytus, provided with young crickets; those of the Odynerus, fed upon larvae of the Chrysomela; those of the sand-dwelling Cerceris, endowed with a hecatomb of weevils.  As will be seen, both consumers and consumed offer plenty of variety.  Well, in every case their proper diet, seasoned with honey, is fatal.  Whether poisoned or disgusted, they all die in a few days.

A strange result!  Honey, the nectar of the flowers, the sole diet of the apiary under its two forms and the sole nourishment of the predatory insect in its adult phase, is for the larva of the same insect an object of insurmountable disgust, and probably a poison.  The transfiguration of the chrysalis surprises me less than this inversion of the appetite.  What change occurs in the stomach of the insect that the adult should passionately seek that which the larva refuses under peril of death?  It is no question of organic debility unable to support a diet too substantial, too hard, or too highly spiced.  The grubs which consume the larva of the Cetoniae, for example (the Rose-chafers), those which feed upon the leathery cricket, and those whose diet is rich 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.