164 INSECTS AND HEREDITY 



that alluded to in the discussion of the cocoon-making 

 instinct. It implied a gift of prophecy, a knowledge of 

 what would happen to offspring after the burrow had 

 been sealed and the inmate left to its fate. 1 



Another powerful argument is derived from the com- 

 parison between the instincts which are performed but 

 once and those which are performed many times in a 

 single life. Various elaborate performances are under- 

 taken but once in an insect's lifetime, and thus are always 

 ' prior to individual experience '. 2 The behaviour which 

 leads to the production of an elaborate cocoon or the 

 burial of a larva in its earthen cell is clearly instinctive, 

 and the most convincing evidence would be required — 

 evidence which it is needless to say is entirely lacking — 

 in order to prove that certain insects which perform an 

 act no more elaborate many times in their lives are guided 

 by anything except the compulsion of a ' nervous system 

 built through heredity '. 3 If the cocoon-making instinct 

 has evolved through selection, the comb-making instinct 

 of the social Hymenoptera has surely arisen in the same 

 way and not through the operation of an entirely different 

 set of causes. 



As a matter of fact, I have witnessed the perfection of 

 comb-building ' prior to individual experience ' and under 

 conditions which prevented the worker from profiting by 

 the experience of others. I have seen ' the worker of 

 a species of Vespa freshly emerged from the pupa, and 



1 The argument was used in the Discussion on Acquired Characters in 

 Section D of the British Association at Newcastle, Friday, September 13, 

 1889. See Report, p. 620, where, however, only the title of the paper is 

 printed. The following sentences are quoted from the abstract in Nature, 

 vol. xl, 1889, p. 610: — 



' With regard to instinct, Dr. Romanes had suggested a difficulty— that 

 was, the instinct of certain wasps to sting and paralyze the nerve centres 

 of their prey. But it must be remembered that the benefits arising from 

 this instinct were felt not by the wasps themselves, but by their progeny.' 



In Proc. Boston Soc. Nat. Hist., vol. xxvi, 1895, p. 392 (pp. n8, 119 

 of the present volume), the argument is stated in greater detail. 



2 For instance, the cocoon-making instinct, already alluded to (see 

 pp. 157-60). Weismann has directed particular attention to this 

 argument against a Lamarckian interpretation {The Evolution Theory, 

 London, 1904, vol. i, pp. 155 et sqq.). 



3 Nature, vol. lxv, 1 90 1 , p. 5 1 . The passage has been slightly modified. 



