352 SPECIAL INSTINCTS. [Chap. VIII. 



**"SB-aist*iral 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 diificult: cells constructed like those 

 of the bee or the wasp gain in strength, and save much 

 in labour and space, and in the materials of which they 

 are constructed. With respect to the formation of wax, 

 it is known that bees are often hard pressed to get suffi- 

 cient 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 pro- 

 digious quantity of fluid nectar must be collected and 

 consumed by the bees in a hive for the secretion of the 

 wax necessary for the constru'ction 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 sup- 

 ported. Hence the saving of wax by largely saving 

 honey and the time consumed in collecting the honey 

 must be an important element of success to any family of 

 bees. Of course the success of the species may be de- 

 pendent on the number of its enemies, or parasites, or 

 on quite distinct causes, and so be altogether independ- 

 ent of the quantity of honey which the bees can collect. 

 But let us suppose that this latter circumstance deter- 

 mined, as it probably often has determined, whether a 



