In considering the physiology of the bee, the first function that claims our notice is that of Nutri tion. The food of bees is principally of two kinds; namely, the fluid secretions of vegetables contained in the nectarea of the flowers, and the dust of the anthers:, which has been termed by botanists the pollen, but which, when collected by the bees, has received a variety of appellations, .such as farina, bee-bread, raw wax (cire-brute), &c. Occasionally, however, we find bees feeding upon other saccharine substances besides honey, such as honey-dew, treacle, syrup, &c.
The organs by which they collect food are ex tremely complex, for they comprise instruments adapt-1 ed to the reception of liquid aliment, as well as those fitted for the division of solid materials. Reaumur has given the most elaborate description of these or gans, in which he has corrected some errors that Swammerdam had fallen into. For the purpose of taking up fluids they are provided, in common with all hymenopterous insects, with a long and flexible proboscis or trunk, which may be considered as a lengthened tongue, though, strictly speaking, it is formed by a prolongation of the under lip. It is not tubular, as Swammerdam had supposed, but solid throughout, and the minute depression at its ex tremity is not the aperture of any canal through which liquids can be absorbed. Cuvier, in his LecONS Anatomie Con:parer, has not marked this dis tinguishing feature in the proboscis of the bee, but speaks of it in common with the tubular trunks of the other hymenoptera, and describes its aperture as being situated in the lower part. But Resumer has very satisfactorily shown that the trunk of the bee performs strictly the office of a tongue, and not that of a tube for suction, for when it takes up honey or other' fluid aliment, the under or the upper surfaces are more immediately applied to it, and rolled from side to side, and bee thus licks up what adheres to it, while the extremity of the trunk it frequently not applied at all to the substance ta ken up. The trunk is supported on a pellicle which admits of being bent back, or propelled forwards, and thus can retract or stretch out the trunk to a considerable extent. Protection is given to it by a double sheath ; the external consisting of two scales furnished by the expansion of one of the portions of the labial palpi, and the internal, formed by the pro longation of the two external portions of the jaw. The whole member thus consists of five principal parts, on which account Fabricius termed it lingua quinquefida.
For the purpose of mechanically dividing solid materials, the mouth is furnished with two strong mandibles and four palpi; they are but little em ployed in eating, but are of great use in enabling the insect to seize and break down hard substances for other purposes. In the working-bee all these parts are of larger dimensions than in the other kinds. The teeth are two in number, and have the
form of concave scales with sharp edges; they are fixed to the ends of the and play horizontally as in other insects. Reaumur describes and deli neates a large aperture above the root of the pro boscis, which is so surrounded with fleshy parts as not to be readily seen, unless the proboscis be ex tended and bent downwards. This he considers as the mouth or orifice of the gullet ; on the upper side of which, and of course opposite to the root of the proboscis, a small fleshy and pointed organ is seen, which he regards as the tongue, assisting in the de glutition of the food. Through this orifice, it is presumed, all the aliment, whether liquid or solid, passes ; the former being conveyed to it by the trunk, which, by its contractile power, presses for ward the fluids it has collected between itself and the inner sheath, and the latter being received di rectly after its comminution by the teeth, behind which it is situated. Latreille, however, whose au thority is great on a point of this nature, thinks that Reaumur has deceived himself with regard to such an aperture, and disbelieves its existence. He con ceives that the food simply passes on by the sides of the tongue, finding its way from thence into the cesopliagus, and so on to the stomach.
The bee has two stomachs : The first is a large transparent membranous bag, pointed in front, and swelling out into two pouches behind. It performs an office, in some respects, analogous to that of the crop in birds ; for it receives, and retains for a time, the fluid of the nectarea, which does not appear to differ, in any respect, from honey. Mr Hunter ob serves, that, whatever time the contents of this re servoir may be retained, he never found them alter ed, so as to give the idea of digestion having taken place. The coats of this reservoir are muscular, by which means it is capable of throwing up the honey into the mouth, so that it is regurgitated into the honey cells, or imparted 'to other bees. None of it ever riasses out from the extremity of the trunk, as Swammerdam had believed. For the purpose of di gestion, a second stomach is provided, which takes its origin from the middle of the two posterior lobes of the former, • and is of a lengthened cylindrical shape. Its communication with the intestine is not direct, but takes place by a projecting or inverted pylorus, thickest at its most projecting part, with a very small opening in the centre, of a peculiar con struction. This inward projecting part is easily seen through the coats of the reservoir, especially if full of honey. A similar kind of structure takes place at the communication of the first with the second stomachs, and, having the properties of a valve, must effectually prevent all regurgitation from the latter into the former.