74 THE FLEA [CH. 



opposite each other, so that they cannot touch or 

 part. Each is pointed in an opposite direction, and 

 tries to run away. A rotary motion ensues which, to 

 the spectators if not to the fleas, is very like waltzing. 



CHAPTER VI 



THE CHIGOES AND THEIR ALLIES 



THE chigoes and their allies belong to a group of 

 fleas sufficiently remarkable to deserve a somewhat 

 detailed account. The reader may remember that 

 they form a family to which the name of Sarcopsyl- 

 lidce has been given. They are the most completely 

 parasitic of any fleas ; and the South American chigoe 

 (Dermatophilus penetrans) enjoys the distinction of 

 being the first foreign flea ever described. This 

 pestilent insect, of which the female has the habit 

 of burrowing into the flesh of the host, soon made 

 itself known to the early travellers in the tropics of 

 America. Oviedo, the Spaniard and historiographer 

 of South America, in his Historia General y Natural 

 de las Indias (1551), seems to have been the first 

 European author who mentions it. After this the 

 chigoe is referred to by writers of various nationalities 

 in many works which were published during the 

 sixteenth, seventeenth and eighteenth centuries. It 

 is an insect which appears under a vast number of 



