862 



SIPHONAPTERA AND COLEOPTERA 



Dermatophilus penetrans Guerin, 1838. 



Synonyms. — Pulex minimus cutem penetrans Catesby , 1743 ; Pulex 

 minutissimiis nigricans Barrere, 1743; Acarus fuscus sub cutem 



nidulans proboscicB acutiore 

 P. Brown] 1756 ; Pulex pene- 

 trans Linnaeus, 1767 ; Rhyn- 

 choprion penetrans Oken, 

 1815. 



This is the insect vari- 

 ously kaown as the Chigoe, 

 or jigger, and beHeved to 

 have been discovered by 

 Oviedo in 1551. The home 

 of this Httle insect appears 

 to be South America, 

 especially Brazil, from 

 which it was conveyed to 

 West Africa about the 

 middle of last century, 

 'arriving on the West Coast 

 Fig. Dermatophilus penetrans : Male. Loandafrom Rio Janeiro 



(MicROPHOTOGRAPH.) by a ship, the Thomas 



Mitchell, in 1872, whose 

 crew was suffering from jiggers. It was probably noted on the 

 Gold Coast for the first , time in the early seventies. It appears 

 to have spread across 

 Africa by Stanley's Expe- 

 dition and by trade routes, 

 arriving in East Africa in 

 1895, and from East Africa 

 it spread to India in 1899 

 by the 4th Bombay In- 

 fantry, but luckily the 

 infection did not spread 

 beyond Bombay. In 1900 

 it reached Madagascar. It 

 affects not merely man, 

 but domestic and wild 

 animals. Perhaps the most 

 noted feature is the way in 

 which it attacks pigs. On 

 the Gold Coast it appeared 



to be largely kept in exist- -piG. 454. — Dermatophilus penetrans 

 ence by these animals. It Female. (Microphotograph.) 



is very easily captured in 



the free state by taking a little pig with a pale abdomen, and 

 placing it on its back on the ground on which infected pigs are 

 living. After watching a few moments, a black speck will appear 



