For the functions and habits of bees we must also refer to the passages already instanced, as well as to the sections above on the "The Queen," etc., that on "The Rationale of Swarming" (page 72), and to those in Chapter VI. on the four substances which bees collect or secrete, as well as (though in a less degree) to those headed "Pasturage" and "General Remarks." Those who will favour our book with a consecutive reading will, we trust, find at the conclusion that all the more important and interesting facts of this class are in one or other of these places tolerably though briefly described. The service that bees perform to flowers is a subject that has attracted much attention of late years. As every one knows, or should know, a flower has its stamens and pistils, which are respectively its male and female organs, and the pollen contained in the anthers, or little knobs on the summits of the stamens, must be conveyed to the pistils, or no seed will be produced. When the anthers burst; the pollen might happen to fall partly on the pistils, or it might not; but the visits of bees (though they do not roll about in the flower, in the manner that some have stated) are found by experience to be efficacious in conveying this dust to the right spot. Owners of fruit trees have noticed, in a season generally unfavourable to the orchard, that if during only one fine forenoon the bees had spread freely amongst the blossoms of a particular tree, that tree would prove more fruitful than its fellows. On this account the orchard is a good place for the apiary, for it seems that the more abundant the honey the better will be the crop of fruit. The whole subject is scientifically treated in Mr. Darwin's remarkable book, "The Fertilisation of Orchids," but we must add to the foregoing how much more urgent are the services of bees in the case of what are termed monœcious and diœcious plants, the former of which have the stamens and pistils _in different flowers_, and the latter have these flowers _upon different roots_. A familiar example of the former is found in the nut tree, whose long catkins, hanging like caterpillars in the early spring, are assemblages of male flowers; while the females, from which the nuts develop, may be detected by their crimson pistil-tips (stigmas), and grow in stalkless clusters of two or three in the openings of remote scaly buds. But for the visits or bees, our autumn nutting rambles would thus have but little prospect of success. In the second case, often very considerable distances intervene between the two flowers; for instance, with the common dog mercury (_Mercurialis perennis_), a botanist may find plantation after plantation containing male flowers by thousands, but not a single female; and at length in some far-off spot he may succeed in finding the females, equally by themselves, yet in full seed. In these cases there is nothing but the visits of pollen-gathering insects