Closely connected with the digestive apparatus is that which is concerned in the making of wax. By pressing the abdomen of the bee, so as to cause its extension, there can be seen, on the under side of the four medial ventral segments, two trapeziform whitish pockets, one on either side of the _carinæ_, or elevated central part. These are of a membranous texture, and are covered with a reticulation of hexagonal meshes, reminding one of the inner coat of the second stomach of the sheep, and other ruminating animals. There is no direct communication between the stomach and these pockets; but Hunter suggested that the secreting surface is in the membrane just alluded to. [Illustration: Fig. 36.--Under Side of Abdomen, Showing Wax Scales.] [Illustration: Fig. 37.--Bee, Showing the Wax Scales.] [Illustration: Fig. 38.--Scales.] We cannot follow the process by which the change from honey to wax is effected, any more than we can account for the elaboration of bile, saliva, and the pancreatic liquid, from our blood by the different organs connected with their production. All we can say is, that the membrane of the wax-receptacles is endowed with the peculiar power of transforming the nectar of flowers into an oil. The actual chemical change may be stated in general terms thus: Honey and sugar contain, roughly speaking, equal chemical equivalents of oxygen, carbon, and hydrogen. In wax, the quantities of the first of these elements is diminished to about an eighth part, while the carbon and hydrogen are more than quadrupled. In other words, the saccharine material suffers very great de-oxidation in passing into the condition of wax. The wax-oil, when it has filled the pocket in which it is secreted, passes out of the body of the insect in _laminæ_ or scales, which take the shape of the bags in which they have been produced. In contact with the air, the wax absorbs a small quantity of oxygen, and loses an equal amount of carbon. When about to be used by the bee, it is picked off the under segments of the body by the hind-legs, passed on to the fore-feet, and by them is conveyed to the mouth, where, by being mixed with saliva and well kneaded, it is rendered pliant, ductile, and more tenacious. The reproductive organs of the queen consist, first, of two large bags, one on each side of the abdomen, and called ovaries, in which the eggs are generated. When mature, these eggs pass by a tube from each ovary to a common duct, on one side of which is found a small yellow vesicle, called the _spermatheca_. On examination under the microscope, this is found to be filled with a viscous fluid, in which, with a lens of high power, may be seen moving thousands of spermatozoa derived from the drone. [Illustration: Fig. 39.--Ovaries and Spermatheca of Queen.]