The Life of the Caterpillar 



And, first of all, does the Pine Procession- 

 ary possess a special glandular structure 

 which elaborates the virus, as do, for in- 

 stance, the poison-glands of the Wasps and 

 Bees? By no means. Anatomy shows that 

 the internal structure of the stinging cater- 

 pillar is similar to that of the harmless one. 

 There is nothing more and nothing less. 



The poisonous product, of unlocalized ori- 

 gin, results, therefore, from a general process 

 in which the entire organism is brought into 

 play. It should, in consequence, be found in 

 the blood, after the manner of urea in higher 

 animals. This is a suggestion of grave im- 

 port, but after all quite valueless without the 

 conclusive verdict of actual experiment. 



Five or six Processionaries, pricked with 

 the point of a needle, furnish me with a few 

 drops of blood. I allow these to soak into a 

 small square of blotting-paper, which I then 

 apply to my fore-arm with a waterproof 

 bandage. It is not without a certain anxiety 

 that I await the outcome of the experiment. 

 The result will show whether the conclusions 

 already forming in my mind will receive a 

 solid basis or vanish into thin air. 



At a late hour of the night, the pain wakes 



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