448 MEDICAL ENTOMOLOGY 



sedentary habit of life. The feeble development of the legs may in 

 part account for the reduction of the thoracic segments. 



Jordan and Rothschild give the following key to the three genera of 

 the family ; altogether fourteen species have been recorded up to the 

 present time. 



JORDAN AND ROTHSCHILD'S KEY TO THE GENERA 

 OF THE SARCOPSYLLIDAE 



1. Rostrum consisting of two segments. Hind coxa produced 



into a tooth at apex. Hind femur simple 2 



Rostrum consisting of three segments. Head not divided by a 

 groove or internal thickening from the antennal groove up- 

 wards. Hind femur produced ventrally at the base into a 

 prominent hook, behind which the femur is deeply sinuate. 

 Hind coxa without patch of spines on the inner side . . Hectopsylla. 



2. Head not divided by a groove or internal thickening from the 



antennal groove upwards. Thoracic tergites in the dorsal 

 line less than half the length of the first abdominal tergite. 

 No patch of spines on the inner side of the hind coxa. 



Female without anal stylet Dermatophilus. 



Head divided by a groove or internal thickening from the 

 antennal groove upwards. Patch of spines on the inner side 

 of the hind coxa. Anal segment of female with stylet . Echidnophaga. 



GENUS DERMATOPHILUS, GUERIN 



(Syn. Sarcopsylla, Westwood ; Rhynchoprion, Karsten, 

 also Baker, 1905.) 



This genus contains two species, penetrans and caecata ; Rothschild 

 gives the following key for their identification : 



Eye distinct ; head and thorax of pregnant female outside the 



abdomen penetrans. 



Eye vestigial ; head and thorax of the pregnant female 

 completely covered by the abdomen, lying in a cavity formed 

 by the latter ......... caecata. 



Dermatophilus penetrans, L., is well known under various names, 

 such as ' Jigger ', ' Chigoe ', ' Nigua ', ' Pique ', or ' sand flea ', as a para- 



The J'tt Fi s '* e ^ man> Apparently it was originally an inhabitant 

 of South America, but on account of its peculiar habit 

 it is well adapted to spread to wherever the climate and local conditions 

 will permit of its existence. It occurs on the west and east coasts of 

 Africa, and has been carried inland from there ; it is common in the 

 West Indies, and occurs also in Madagascar. It has been introduced 

 into Bombay and Karachi with infected sailors, but owing to the great 



