The Life of the Caterpillar 



found in abundance in the old nests, to soak 

 for two days in sulphuric ether. The liquid, 

 coloured as it is with the chlorophyll of the 

 caterpillar's food, turns a dirty green. Then 

 I repeat precisely the process which I men- 

 tioned when I wanted to prove the innocuous- 

 ness of the hairs deprived of their poisonous 

 varnish. I refer to it a second time in order 

 thoroughly to explain the method pursued and 

 to save repetition in the various experiments 

 undertaken. 



The infusion is filtered, spontaneously eva- 

 porated and reduced to a few drops, with 

 which I soak my stinger. This consists of a 

 small piece of blotting-paper, folded in four 

 to increase the thickness of the pad and to 

 give it a greater power of absorption. An 

 area of a square inch or less suffices; in some 

 cases it is even too much. A novice in this 

 kind of research-work, I was too lavish with 

 the liniment; and in return for my generosity 

 I had such a bad time that I make a point of 

 warning any reader desirous of repeating the 

 experiment upon his own person. 



Fully soaked, the square of paper is applied 

 to the fore-arm, on the inner surface, where 

 the skin is more tender. A sheet of rubber 

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