64 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I23 



apparently very weakly sclerotized ; unapparent in single specimen 

 examined. 



Female. — Spermatheca (fig. lOO, SP.) with more heavily sclero- 

 tized body than is usual in genus and insertion of tail more definitely 

 delineated. Posterior margin of seventh sternum (fig. lOo) with 

 elongate upper lobe; oblique below this to rounded posteroventral 

 lobe. Anal stylet 3^ times as long as broad with one apical and one 

 subapical bristle. 



Types. — From Rattus norvegicus {=Epimys decumanus), Simla, 

 northwest India. 



The range of this species is probably the Himalayas, including 

 northern India, southwestern China, and northeastern Burma. 



Records of Specimens Examined 



One male from Ratht^ norvegicus (= Epimys decumanus) , northwest Hima- 

 layas, Aug. 8, 1912. One female from Vandeleuria olcracea nilagirica, Kodai- 

 kanal, Palni Hills, south India, elevation 7,000 ft., 1929, B. Fletcher. One 

 female from Rattus confucianus, Kunming, Yunnan Province, China, Aug. 10, 

 1945. U. S. Typhus Commission. 



Discussion of the Aedeagus of Pcromyscopsylla 



A comparative study of the morphology of the aedeagus of the 

 species of Peromyscopsylla not only enables one to homologize the 

 various sclerites involved, but also to name and understand structures 

 that at first glance seem unique or unrecognizable. 



The most characteristic feature of the aedeagus of this genus is the 

 pair of distolateral lobes (fig. 104, DL.L.). No comparable structure 

 exists in the genera whose aedeagi have been studied thus far, although 

 the related genus Paractenopsyllus Wagner, 1938, is similarly modi- 

 fied. The distolateral lobes are undeveloped in Peromyscopsylla 

 tikhomirovae loff, 1946, where they resemble the apicomedian sclerite 

 of many other genera. In the other Peromyscopsylla, the distolateral 

 lobes are much more conspicuous, and extend apicad to the sclerotized 

 inner tube {S.I.T.). They are freely movable flaps, and are articu- 

 lated with the sclerotized inner tube via the fulcrum {FM.), and 

 apparently also are connected with the crochets {CR.), because S.I.T. 

 and the crochets are usually parallel. When DL.L. is inclined ventrad, 

 then S.LT. and CR. are both subvertical in position, instead of being 

 subhorizontal as normally. The various positions assumed make a 

 study of the aedeagus difficult until it is appreciated that these struc- 

 tures are flaps which not only affect the inclination of S.LT. and CR., 

 but also that of the lateral lobes {L.L.). The dorsoapical margins of 



