( cxxv ) 



some of the ancestors of the Sphex were intelligent enough to 

 notice the peculiar effects which followed vipon stinging insects 

 or caterpillars in the particular regions occupied by nerve- 

 centres, and that, in consequence of being habitually guided 

 by their intelligence to sting in these particular regions, their 

 action became hereditary, i. e. instinctive. But if, in accord- 

 ance with post-Darwinian theory, we relinquish this possible 

 guidance by intelligence, and suppose that the whole of this 

 wonderful instinct was built up by natural selection waiting 

 for congenital (i. e. fortuitous) variations in the direction of a 

 propensity to sting, say, the nine nerve-centres of a caterpillar 

 — then it surely becomes inconceivable that such an instinct 

 should ever have been developed at all." * 



Eimer is even more rash in his statements : — "This is one 

 of the most marvellous instincts that exists ; since the wasp 

 operates on various larvae with nervous systems of various 

 forms, she must effect the paralysis in various ways, and 

 even apart from this, she makes a physiological experiment 

 which is far in advance of the knowledge of man. ... It 

 may be suggested that the wasp only paralyzed the larvae in 

 order to carry them more easily ; but even if this were the 

 case, she must, since she now invariably acts in this way, 

 have drawn a conclusion by deductive reasoning. In this 

 case it is absolutely impossible that the animal has arrived 

 at its habit otherwise than by reflection upon the facts of 

 experience." 



Mr. and Mrs. Peckham make the following comment upon 

 this wild passage from Eimer : — " One can hardly be expected 

 to take such statements seriously, since it is certain that the 

 writer has no knowledge of the life-histories of these insects."! 



III. Thirdly, there are those who believe that the instincts 

 in question are to be explained by the operation of natural selec- 

 tion upon hereditary nervous mechanisms, who believe that 

 the Lamarckian principle of the hereditary transmission of 

 education has never come into the history at any stage. 

 Fabre's observations are quite consistent with this view ; in 



* "Nature," vol. xxxix, 1888, p. 77. 



t "The Instincts and Habits of the Solitary Wasps," by George W. 

 and Elizabeth G. Peckham, Madison, Wis., 1898, p. 221. 



