" Natural Selection " 63 



the absurdity of the idea that natural selection could 

 have produced this instinct. It quietly stings the larva 

 in the three nerve centres of the thorax and in the 

 abdomen, and then is able to squeeze in the head, 

 further resistance being now impossible. A complete 

 paralysis is produced from which it cannot recover. 

 It is then carried to a convenient spot and there 

 the egg is deposited and finds a suitable pabulum 

 until such time as it has developed to maturity. 

 Fabre compares the skill of the sand-wasp to that 

 of the " desnucador " in South America, who, by 

 means of a method acquired by instruction and 

 constant repetition, is enabled to kill the cattle previous 

 to deportation, one after another, with enormous 

 rapidity. Fabre comments on this comparison in the 

 following manner i 1 " Now here is the sand- wasp, a 

 slayer of caterpillars by a far more cunning process. 

 Where are the professors of the art of stinging ? There 

 are not any. When the wasp rends her cocoon and 

 issues from under ground, her predecessors have long 

 ceased to live : she herself will perish without seeing 

 her successors. The sand-wasp is born a finished 

 ' desnucador,' even as we are born feeders at the 

 mothers' breast. The nursling uses her suction-pump, 

 the sand-wasp her dart, without ever being taught, 

 and both are past masters of their difficult art from the 

 first attempt. Here we have instinct, the unconscious 

 impulse that forms an essential part of the conditions 

 of life and is handed down by heredity in the same 

 way as the rhythmic action of the heart and lungs." 



The mechanist school, with their blind dogmatism, 

 have a rough time at the hands of this keen observer : 

 " Given half a dozen cells, a bit of protoplasm, and a 

 diagram for demonstration, and they will account to 

 you for everything. The organic world, the intellectual 

 1 " English Review," December, 1912. 



