Besides the three essential members of the bee community, which I have just described, Huber has called the attention of the Apiarian to a fourth kind, which appear to be only casual inmates of the hive, from which however they are soon expelled by the workers. He has called them _black bees_, and says he first noticed them in two of his hives, in the year 1809, and on several other occasions from that time to the year 1813. They present a perfect resemblance to the working bees, excepting in their colour, which, in consequence of their being less downy, appears darker. On dissection, their internal structure also appears to be the same. Huber regards them as imperfect bees, but leaves to future naturalists an inquiry into their nature and origin. Messrs. Kirby and Spence have thrown out a conjecture that these black bees may be _superannuated bees_, that being no longer capable of contributing towards the labours of the community, are banished or destroyed by its younger members. They found their conjecture upon the usual effect of superannuation in rubbing off the hair of insects and thereby giving them a darker hue. It is the office of the queen-bee to lay eggs, which she deposits in cells constructed for their reception by the working bees. These cells vary from one another in size, (and in the instance of the royal cells, they also vary in form), according as they are intended to be the depositories of eggs that are to become drones, or of those that are to become workers. But for a more particular account of these cells, _Vide_ Part II. "Architecture of Bees." The Rev. W. Dunbar, minister of Applegarth, who has recently added some important particulars to our general stock of knowledge respecting bees, states that when the queen is about to lay, she puts her head into a cell, and remains in that position for a second or two, probably to ascertain its fitness for the deposit which she is about to make. She then withdraws her head, and curving her body downwards, inserts her tail into the cell: in a few seconds she turns half round upon herself and withdraws, leaving an egg behind her. When she lays a considerable number, she does it equally on each side of the comb, those on the one side being as exactly opposite to those on the other, as the relative position of the cells will admit. The effect of this is to produce a concentration and œconomy of heat for developing the various changes of the brood. The following sketch is taken from a plate given by Mr. Dunbar in the Edinburgh Philosophical Magazine, to represent the comb upon which his observations were made, and to show that part of it which was occupied by brood, the surrounding part of the square being full of sealed honey. [Illustration]