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BULLETIN 248, U. S. DEPARTMENT OF AGRICULTURE. 



as compared with others, has been briefly outlined in the preceding 

 pages, and control measures, applicable to this and most other species. 

 are discussed in the following pages. 



THE DOG FLEA. 



The dog is undoubtedly the normal host for the flea which is 

 known scientifically as Ctenocephalus cards Curtis (fig. 1) ; neverthe- 

 less the insect is not averse to partaking of a meal of blood from man 

 or a cat, especially when its normal host is not at hand. Like the 



Fig. 6. — The human flea : Adult male. Greatly enlarged. Note the difference in the 

 shape of the abdomen of the male as compared with the female (fig. 5). (Origi- 

 nal.) 



human flea, this species has a wide distribution throughout the world ; 

 in fact, it is generally considered the most widely distributed species 

 of flea. 



As an annoy er of man the dog flea ranks next to the human flea. 

 In the eastern United States, as has been pointed out by Dr. Howard, 

 instead of the human flea this is the species usually reported as infest- 

 ing houses. In some instances reported to the Bureau of Entomology 

 houses have been rendered almost uninhabitable by this aggressive 

 insect. The most severe infestations, as reported by Dr. Howard, 

 have occurred in cases where dwellings have been closed up during 

 summer, and when opened upon returning the occupants were greeted 



