The Life of the Caterpillar 



Processionary on becoming a chrysalis and 

 sometimes the shrivelled caterpillar turned 

 into a sort of chalky cylinder through the 

 invasion of the malignant fungus. Six 

 months later, these wretched cocoons were still 

 capable of producing redness and irritation. 



Examined under the microscope, the russet 

 hairs, the cause of the itching, are stiff rods, 

 very sharp at either end and armed with barbs 

 along the upper half. Their structure has 

 absolutely nothing in common with nettle- 

 hairs, those tapering phials whose hard point 

 snaps off, pouring an irritant fluid into the 

 tiny wound. 



The plant from whose Latin name, Urtica, 

 we derive the word urtication borrowed the 

 design of its weapon from the fangs of the 

 venomous serpents; it obtains its effect, not 

 by the wound, but by the poison introduced 

 into the wound. The Processionary employs 

 a different method. The hairs, which have 

 naught resembling the ampullary reservoir of 

 the nettle-hairs, must be poisoned on the sur- 

 face, like the assegais of the Kafirs and 

 Zulus. 



Do they really penetrate the epidermis? 

 Are they like the savage's javelin, which can- 



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