SIPHONAPTERA OF THE PHILIPPINE ISLANDS. 121 



Ctenocephalus felis Bouche. 



Some yeais ago the writer had an opportunity to study a col- 

 lection of fleas taken off a dog, in Cebu, Philippine Islands, 

 and was surprised to find that all the specimens conformed to 

 the type C. felis. There is a statement appearing somewhere, 

 although the reference is forgotten, that an observer in India 

 doubted the correctness of Rothschild's separation of Ctenoce- 

 phaliis canis and CtntoccpJialas felis, believing them to Vje iden- 

 tical. He, however, upon being given an opportunity to see a 

 specimen of C canis, realized that the separation was quite 

 proper and that his reasons for doubt lay in the fact that in 

 India C. canis did not exist and that he had, therefore, never 

 seen any but C. felis. 



Further studies, in the Philippine Islands, of specimens of 

 Ctenocephalus from the dog, cat, rat, domestic rabbit, man, and 

 of some taken from the floor of a house, indicate that Ctenoce- 

 phalus canis does not exist in the Philippines. The specimens 

 from man were collected in Baguio having an altitude of about 

 1,400 meters and with a temperature nearly approximating that 

 of the temperate zone. The rest were secured in Manila. 



The identification as C. felis was based upon the following 

 characteristics as pointed out by Rothschild. ** 



The head, of the female especially, is compressed and elon- 

 gated, in a few, however, less so than in others, and therefore 

 more nearly approaching C. ca7iis in this respect. 



Bristles on epimerum of metathorax never more than 8 in 

 first row nor more than 7 in second row. 



Bristles on metathoracic episternum never more than 3, and 

 in the majority of instances 2 only. 



Bristles on inner side of hind femur never more than 10. 

 There is only a single bristle, and a small hair, situated between 

 the fifth pair and apical group of bristles on the posterior border 

 of the hind tibia. In this series of C. felis studied, there was 

 also a constant absence of the third pair of bristles, this pair 

 being represented by a single bristle and a small hair, or more 

 frequently 1 or sometimes 2 small hairs only. In this respect 

 specimens of C. felis in the Philippine Islands seem to differ 

 from those of C. felis found in the United States and Europe, 

 which have a pair of bristles in this location. 



The movable finger has its dorsal edge quite rounded and 



* Ent. Rec. and Joiirn. of Variation (1901), 13; and Novit. Zool. 

 (1905), 12. 



