THE FLEAS FOUND ON DOMESTIC KATS AND MICE. 



93 



6. Genus Hoplopsyllus, Baker. 



Nearly related to Pule.v. At once recognised by the protliorax bearing a 

 comb, as in Ceratopliylhis. The club o£ the antenna is segmented only on 

 the hind side^ as in Puled' and Xenopsf/Ua, the first midtarsal segment is 

 much shorter than the second, and the fifth tarsal segment in all the tarsi has 

 four bristles on each side, besides a thin and long subapical hair. North 

 American fleas; one species found on rats, but only once. 



1. H. anomalus, Baker. The comb of the prothorax consists of about 8 to 

 10 spines. — Colorado and California. 



7. Genus Ctenocephalus, Kolen. 



Two species, which, although confounded by many authors, are easily 

 distinguished by the shape of the head. 



1. Ct. canis, Dugcs. Frons of the head strongly rounded (fig. 12, S)- 

 Manubrium of clasper of (^ widened at the end.— The flea commonly found 

 on the dog, but also occurring on rats. Practically cosmopolitan, but more 

 abundant in temperate countries than in the tropics. 



2. Ct. felis, Bouche. Frons of the head much less rounded than in catiis, 

 the head therefore longer (fig. 13, S). Manubrium of the clasper (<^) only 

 a little widened at the apex. — A widely distributed and very common flea all 

 over the world on rats as well as many other animals. 



