I took several small fir boxes, a foot square and fifteen lines wide, and joined them together by hinges, so that they could be opened and shut like the leaves of a book{B}. When using a hive of this description, we took care to fix a comb in each frame, and then introduced all the bees necessary for each particular experiment. By opening the different divisions successively, we daily inspected both surfaces of every comb. There was not a single cell where we could not distinctly see what passed at all times, nor a single bee, I may almost say, with which we were not particularly acquainted. Indeed, this construction is nothing more than the union of several very flat hives which may be separated. Bees, in such habitations, must not be visited before their combs are securely fixed in the frames, otherwise, by falling out, they may kill or hurt them, as also irritate them to that degree that the observer cannot escape stinging, which is always painful, and sometimes dangerous: but they soon become accustomed to their situation, and in some measure tamed by it; and, in three days, we may begin to operate on the hive, to open it, remove part of the combs, and substitute others, without the bees exhibiting too formidable symptoms of displeasure. You will remember, Sir, that on visiting my retreat, I shewed you a hive of this kind that had been a long time in experiment, and how much you were surprised that the bees so quietly allowed us to open it. In these hives, I have repeated all my observations, and obtained exactly the same results as in the thinnest. Thus, I think, already to have obviated any objections that may arise concerning the supposed inconvenience of flat hives. Besides, I cannot regret the repetition of my labours; by going over the same course several times, I am much more certain of having avoided error; and it also appears, that some advantages are found in these which may be called _Book_ or _Leaf-hives_, as they prove extremely useful in the economical treatment of bees, which shall afterwards be detailed. I now come to the particular object of this letter, the fecundation of the queen bee; and I shall, in a few words, examine the different opinions of naturalists on this singular problem. Next I shall state the most remarkable observations which their conjectures have induced me to make, and then describe the new experiments by which I think I have solved the problem{C}.