108 MISC. PUBLICATION 5 0, U. S. DEPT. OF AGRICULTURE 



pointed apically. Hind coxa with a row or patch of spinelets on inner surface. 

 Femora with very few or no lateral setae. Segment V of each tarsus with 4 

 pairs of lateral plantar bristles. Abdomen without apical spines. Sternal 

 plate VIII of male large, broad, setigerous, unmodified. Sternal plate IX of 

 male with an anterior whiplike apophysis, a poorly sclerotized pair of inner, 

 vertical processes, and a simple pair of distal lobes. 



Members of this genus were probably originally confined to Africa. 

 Two species, cants Curtis and felis Bouche, have been introduced into 

 many parts of the world. 



Ctenocephalides canis (Curtis) 



(Fig. 12, F) 



Pulex canis Curtis, 1826, British Ent, vol. 3, No. 114. 



Ctenocephalides canis Stiles and Collins, 1930, U. S. Pub. Health Serv. Epts. 

 45: 1308. 



Type host. — Not indicated. 



Type locality — Not indicated. 



Range. — Almost cosmopolitan, but being apparently absent in cer- 

 tain regions inhabited by man although occurring on certain wild 

 carnivores in areas not yet reached by man. 



In their summary of the distribution of Ctenocephalides canis in 

 the United States Trembley and Bishopp (76) record this flea from 

 31 States and the District of Columbia. The Rocky Mountain and 

 Intermountain regions are not represented. Hosts for which two or 

 more records are given include dog, man, cat, and gray fox. 



Typical forms of Ctenocephalides canis are distinguished from 

 those of C. felis in having a much shorter forehead and in having 

 spine I of the head comb very distinctly shorter than spine II, while 

 in C. felis spine I is about equal in length to spine II. In C. canis, 

 as well as in C. felis, there are certain sexual differences in the head 

 characters. These are shown in some figures by I. Fox (25, p. ll^l). 



Ctenocephalides canis is an important intermediate host of the dog 

 tapeworm, Dipylidium caninum, a species very common in dogs and 

 cats and occasionally found in man. C. canis has also been reported 

 as an intermediate * host of the following parasites : Hymenolepis 

 •diminuta, Dirofilaria immitis, LeUhmanma donovani, and L. infan- 

 tum. This flea may be of importance in the transmission of plague 

 during epidemics. 



The complete life cycle of Ctenocephalides canis is passed in from 

 2 to 4 weeks, which means that there may be several generations in 

 a year in the warmer sections of the world. Bacot (1) found that 

 €. canis would live as long as 234 days when fed exclusively on man. 



Three synonyms of this species are listed in Wagner's catalog (80) . 



Ctenocephalides felis (Bouche) 

 (Figs. 1 and 2) 



Pulex felis Bouche\ 1835, Nova Acta Phys.-Med. Acad. Caes. Leop. Carol. 



17: 505, fig. 2. 

 Ctenocephalides felis Stiles and Collins, 1930, U. S. Pub. Health Serv. Rpts. 



45: 1309. 



Type host. — "Housecat." 

 Type locality. — Not indicated. 



