286 ORIGIN OF SPECIES 



by the bees — as delicately as a painter could have done it 

 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 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 adjoin- 

 ing 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 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 were to work alternately on the in- 

 side 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. 



