SECTION 22. OBSERVATION. 325 



respect to the formation of wax, 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 proved that from twelve to fifteen pounds of 

 dry sugar are consumed by a hive of bees for the secretion of a 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 neces- 

 sary 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, and the time consumed in collecting the hone^y, must be 

 an important element of success to any family of bees. Of course, the 

 success of the species may be dependent on the number of its enemies, 

 or parasites, or on quite distinct causes, and so be altogether independent 

 of the quantity of honey which the bees can collect. But let us suppose 

 that this latter circumstance determined, as it probably often has deter- 

 mined, whether a bee allied to our humble-bees could exist in large 

 numbers in any country ; and let us further suppose that the community 

 lived through 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 imaginary humble-bee, if a slight modification of her instinct led her 

 to make her waxen cells near together, so as to intersect a little; for a 

 wall in common even to -two adjoining cells would save some little labour 

 and wax. Hence it would continually be more and more advantageous 

 to our humble-bees, if they were to make their cells more and more 

 regular, nearer together, and aggregated into a mass, like the cells of the 

 Melipona; for in this case a large part of the bounding surface of each 

 cell would serve to bound the adjoining cells, and much labour and wax 

 would be saved. Again, 'from -the same cause, it would be advantageous 

 to the Melipona, if she were to make her cells closer together, and more 

 regular in every way than at present; for then, as we have seen, the 

 spherical surfaces would wholly disappear and be replaced by plane 

 surfaces ; and the Melipona would make a comb as perfect as that of 

 the hive-bee. Beyond this stage of perfection in architecture, natural 

 selection could not lead ; for the comb of the hive-bee, as far as we can 

 see, is absolutely perfect in economising labour 'and wax. 



"Thus, as I believe, the most wonderful of all known instincts, that 

 of the hive-bee, can be explained by natural selection having taken 

 advantage of numerous, successive, slight modifications of simpler instincts, 

 natural selection having, by slow degrees, more and more perfectly led 

 the bees to sweep equal spheres at a given distance from each other in 

 a doublB layer, and to build up and excavate the wax along the planes of 

 intersection; the bees, of course, no more knowing that they swept their 

 spheres at one particular distance from each other, than they know what 

 are the several angles of the hexagonal prisms and of the basal rhombic 

 plates ; the motive power of the process of natural selection having been 

 the construction of cells of due strength and of the proper size and shape 

 for the larva?, this being effected with the greatest possible economy 

 of labour and wax; that individual swarm which thus made the best 

 cells with least labour, and least waste of honey in the secretion of wax, 

 having succeeded best, and having transmitted their newly acquired 

 economical instincts to new swarms, which in their turn will have had 

 the best chance of succeeding in the struggle for existence." (The Origin 

 of Species, final edition, chapter 8.) 



