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Huber's statement that the very first cell is excavated out of a little parallel…sided wall of wax； is not； as far as I have seen； strictly correct； the first commencement having always been a little hood of wax； but I will not here enter on these details。 We see how important a part excavation plays in the construction of the cells； but it would be a great error to suppose that the bees cannot build up a rough wall of wax in the proper position that is； along the plane of intersection between two adjoining spheres。 I have several specimens showing clearly that they can do this。 Even in the rude circumferential rim or wall of wax round a growing comb； flexures may sometimes be observed； corresponding in position to the planes of the rhombic basal plates of future cells。 But the rough wall of wax has in every case to be finished off； by being largely gnawed away on both sides。 The manner in which the bees build is curious； they always make the first rough wall from ten to twenty times thicker than the excessively thin finished wall of the cell； which will ultimately be left。 We shall understand how they work； by supposing masons first to pile up a broad ridge of cement； and then to begin cutting it away equally on both sides near the ground； till a smooth； very thin wall is left in the middle； the masons always piling up the cut…away cement； and adding fresh cement； on the summit of the ridge。 We shall thus have a thin wall steadily growing upward； but always crowned by a gigantic coping。 From all the cells； both those just commenced and those completed； being thus crowned by a strong coping of wax； the bees can cluster and crawl over the comb without injuring the delicate hexagonal walls； which are only about one four…hundredth of an inch in thickness； the plates of the pyramidal basis being about twice as thick。 By this singular manner of building； strength is continually given to the comb； with the utmost ultimate economy of wax。
It seems at first to add to the difficulty of understanding how the cells are made； that a multitude of bees all work together； one bee after working a short time at one cell going to another； so that； as Huber has stated； a score of individuals work even at the commencement of the first cell。 I was able practically to show this fact； by covering the edges of the hexagonal walls of a single cell； or the extreme margin of the circumferential rim of a growing comb； with an extremely thin layer of melted vermilion wax； and I invariably found that the colour was most delicately diffused by the bees as delicately as a painter could have done with his brush by atoms of the coloured wax having been taken from the spot on which it had been placed； and worked into the growing edges of the cells all round。 The work of construction seems to be a sort of balance struck between many bees； all instinctively standing at the same relative distance from each other； all trying to sweep equal spheres； and then building up； or leaving ungnawed； the planes of intersection between these spheres。 It was really curious to note in cases of difficulty； as when two pieces of comb met at an angle； how often the bees would entirely pull down and rebuild in different ways the same cell； sometimes recurring to a shape which they had at first rejected。
When bees have a place on which they can stand in their proper positions for working； for instance； on a slip of wood； placed directly under the middle of a comb growing downwards so that the comb has to be built over one face of the slip in this case the bees can lay the foundations of one wall of a new hexagon； in its strictly proper place； projecting beyond the other completed cells。 It suffices that the bees should be enabled to stand at their proper relative distances from each other and from the walls of the last completed cells； and then； by striking imaginary spheres； they can build up a wall intermediate between two adjoining spheres； but； as far as I have seen； they never gnaw away and finish off the angles of a cell till a large part both of that cell and of the adjoining cells has been built。 This capacity in bees of laying down under certain circumstances a rough wall in its proper place between two just…commenced cells； is important； as it bears on a fact； which seems at first quite subversive of the foregoing theory； namely； that the cells on the extreme margin of wasp…combs are sometimes strictly hexagonal； but I have not space here to enter on this subject。 Nor does there seem to me any great difficulty in a single insect （as in the case of a queen…wasp） making hexagonal cells； if she work alternately on the inside and outside of two or three cells commenced at the same time； always standing at the proper relative distance from the parts of the cells just begun； sweeping spheres or cylinders； and building up intermediate planes。 It is even conceivable that an insect might； by fixing on a point at which to commence a cell； and then moving outside； first to one point； and then to five other points； at the proper relative distances from the central point and from each other； strike the planes of intersection； and so make an isolated hexagon： but I am not aware that any such case has been observed； nor would any good be derived from a single hexagon being built； as in its construction more materials would be required than for a cylinder。
As natural selection acts only by the accumulation of slight modifications of structure or instinct； each profitable to the individual under its conditions of life； it may reasonably be asked； how a long and graduated succession of modified architectural instincts； all tending towards the present perfect plan of construction； could have profited the progenitors of the hive…bee？ I think the answer is not difficult： it is known that bees are often hard pressed to get sufficient nectar； and I am informed by Mr。 Tegetmeier that it has been experimentally found that no less than from twelve to fifteen pounds of dry sugar are consumed by a hive of bees for the secretion of each pound of wax； so that a prodigious quantity of fluid nectar must be collected and consumed by the bees in a hive for the secretion of the wax necessary for the construction of their combs。 Moreover； many bees have to remain idle for many days during the process of secretion。 A large store of honey is indispensable to support a large stock of bees during the winter； and the security of the hive is known mainly to depend on a large number of bees being supported。 Hence the saving of wax by largely saving honey must be a most important element of success in any family of bees。 Of course the success of any species of bee may be dependent on the number of its parasites or other enemies； or on quite distinct causes； and so be altogether independent of the quantity of honey which the bees could collect。 But let us suppose that this latter circumstance determined； as it probably often does determine； the numbers of a humble…bee which could exist in a country； and let us further suppose that the community lived throughout the winter； and consequently required a store of honey： there can in this case be no doubt that it would be an advantage to our humble…bee； if a slight modi