vn] FLEAS AND PLAGUE 83 



favourite spot of attack. The only remedy is a sharp 

 knife and a little antiseptic wash. Pigs and fowls 

 are sometimes killed by chigoes, and Indians occasion- 

 ally are attacked by lockjaw after the parasite has 

 been removed. But this is not directly attributable 

 to the chigoe. The eggs are laid one by one ; when 

 this operation is completed the mandibles weaken 

 and the shrivelled body of the insect can be rubbed 

 off. But a painful sore may be produced if the 

 parasite is forcibly broken off and the mouth-parts 

 are left in the wound. 



The chigoe (Dermatophttiis penetrans) is a native 

 originally of South America. It ranges from Mexico 

 to Northern Argentina. Some time after the middle 

 of the nineteenth century it was, somehow, carried 

 across the Atlantic and introduced into West Africa. 

 From there it has now spread across the Dark Conti- 

 nent to the Great Lakes, and has even reached 

 Madagascar. Such are the modern facilities of trans- 

 port which parasites are quick to take advantage of. 



CHAPTER VII 



FLEAS AND PLAGUE 



IN order to understand the part played by fleas 

 in the transmission of plague it is necessary to have 

 some clear elementary knowledge of the nature of 



62 



