450 MEDICAL ENTOMOLOGY 



GENUS ECHIDNOPHAGA, OLLIFF. 

 (Syn., Argopsylla, Enderlein, Xestopsylla, Baker). 



This genus includes several species from Asia, South Africa and 

 Australia, and one from Europe. They occur on many mammals and 

 birds, not being restricted to one host. Several species have been found 

 on rats. One, E. gallinaceus (Plate LVI, fig. 3), is the common flea 

 of the domestic fowl, and is found wherever that bird has been in- 

 troduced. 



Echidnophaga is the least specialized genus of the Sarcopsyllidae, the 

 adaptations of structure described above being less marked than in the 

 other genera. The abdomen of the pregnant female does not become 

 very greatly distended, and the sclerites of the abdominal wall are not 

 much separated from one another. 



Rothschild gives the following key to the species : 



1. Fifth tarsal segment with three heavy bristles, one small and 



a long thin subapical hair on each side ........ 2 



Fifth tarsal segment on each side with one heavy sub-basal 



bristle, a thinner median one and a small postmedian hair . liopus 



2. Fifth tarsal segment with two ventral apical bristles ; hind 



edge of head with a lateral lobe gallinaceus 



Fifth tarsal segment with one ventral apical bristle ; hind edge 



of head with a lateral lobe. myrmecobii 



Fifth tarsal segment with one ventral apical bristle ; hind edge 



of head without distinct lateral lobes. .... murina 



All the above have been found on rats. The second species comes 

 from Australia, the third from southern and south-eastern Europe. E. 

 liopus was originally found in Western Australia, on Echidna. It has 

 also been found in India (Agra) on rats. 



FAMILY PULICIDAE 



Rostrum more or less strongly chitinized, consisting of five or more 

 segments, inclusive of the unpaired basal one. Thoracic segments together 

 longer than the first abdominal one. 



This family contains the majority of the fleas. Many of the 

 species are very little known, and are of no special interest to the parasito- 

 logist. The genera may be conveniently, though somewhat empirically, 

 divided into groups, the first of which includes those which have combs 

 on the genal border or on the pronotum, or on both, and may or may 

 not have eyes ; the second includes those which have no combs and 

 always have eyes. The latter form a compact series, including the human 



