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



The female of mesus is easily identified by the peculiar S-shaped 

 receptaculum seminis, which has a slender head and a rather stout 

 tail. 



The Subgenus POLYGENIS Jordan 



Polygenis Jordan, 1939, Novitates Zool. 41 : 444. Type, Pulex roberti Rothschild 

 (by original designation). 



Labial palpus not reaching apex of trochanter I. Prosternum not humped 

 or extending downward anteriorly between the coxae. Mesosternuin not so high 

 as long. Last segment of tarsus III not longer than second segment of tarsus 

 II. Head (body) of receptaculum seminis usually produced dorsally or ante- 

 riorly into a hump. 



One of the outstanding characters of most species of this subgenus 

 is the shape of the head of the receptaculum seminis of the female. 

 It is produced into a hump above or in front. Usually this hump is 

 angulate distally. 



Rhopalopsyllus (Polygenis) dunni Jordan and Rothschild 



Rhopalopsylltis dunni Jordan and Rothschild, 1922, Ectoparasites 1 : 269, figs. 

 261 and 262. 



Type host. — Sigmodon hispidus Say and Ord (cotton rat) . 



Type locality. — Fort Clayton, Canal Zone, Panama. 



Range. — Central America. 



According to Jordan and Rothschild (52) this species is closely 

 related to oohlsi Wagner, but the movable finger is shorter, not reach- 

 ing to the apical bristle of the clasper, and also broader and without 

 a tooth on the dorsal side near the apex. 



Rhopalopsyllus (Polygenis) gwyni C. Fox 



(Fig. 4, B) 



Rhopalopsyllus gwyni C. Fox, 1914. U. S. Pub. Health Serv. Hyg. Lab. Bui. 

 97 : 10, pi. 3, figs. 1-6. 



Type host.— "Rats." 



Type locality. — Brunswick, Ga. 



Range.— Southeastern part of the United States. 



At one time considered as a probable synonym of oohlsi Wagner, 

 this species was shown by Jordan (42, p. 292) in 1932 to be distinct. 

 It and Rhopalopsyllus (Polygenis) sigmodoni Stewart are the only 

 species of the subgenus Polygenis known to occur in the United 

 States. 



Rhopalopsyllus (Polygenis) klagesi samuelis Jordan and Rothschild 



Rhopalopsijllns klagesi samuelis Jordan and Rothschild, 1923, Ectoparasites 

 1 : 331, figs. 342 and 344. 



Type host. — u Didelphis marsupialis" (opossum). 

 Type locality. — San Esteban, Venezuela. 

 Range. — Central and South America. 



The typical variety of Rhopalopsyllus (Polygenis) klagesi occurs 

 in Venezuela and Brazil. 



