From the Unconscious to the Conscious 



sureness of action to strike at once on the right spot 

 by surprise, for the prey is often formidably armed and 

 stronger than the aggressor. 



The poisoned sting must therefore be directed with 

 certainty on the motor nervous centres, and there only. 

 One, two, or several stabs are needed, according to the 

 number or concentration of the nerve-ganglions. This 

 function, so unerringly exercised by the insect, has not 

 been learned. When the hymenopteron tears its cocoon 

 and emerges from underground, its parents and prede- 

 cessors have been long dead, and the insect itself will 

 perish without seeing its progeny or its successors. The 

 instinct cannot therefore be transmitted by example nor 

 by training. It is innate. 



How can the origin of this instinct be explained by 

 any of the classical factors of evolution ? 



Instinct, we are told, is but a habit acquired little by 

 little and transmitted by heredity. 



Fabre laid himself out to demonstrate the impossi- 

 bility of this concept. 



Some sand-wasp in the long distant past, would 

 have reached, by chance, the nerve-centres of a 

 grub, benefiting by the act partly herself by avoiding 

 a struggle not devoid of danger, and partly for her 

 larva, provided with fresh game, alive but harmless. 

 She must then have endowed her race, by heredity, 

 with the propensity to repeat these advantageous 

 tactics. The maternal gift would not have favoured 

 all her descendant's equally . . . then would have 

 followed the struggle for life . . . the weaker 

 would have succumbed, the strong would have 

 prospered, and from age to age, selection in conjunc- 

 tion with life would have transformed the fugitive 

 impression of the first act into the deep, ineffaceable 

 instinct at which we marvel in the hymenoptera of 

 to-day. 



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