NO. 4 FLEA GENUS PEROMYSCOPSYLLA— JOHNSON AND TRAUB 45 



cave to straight; three large bristles near dorsocaudal angle, most 

 ventral may be sinuate ; posterior margin with two notches containing 

 minute bristles ; anterior margin with two to four thin, long bristles. 

 Distal arm of ninth sternum (fig. 80) rather broad; with small trun- 

 cate apex and convex posterior (ventral) margin on which are some 

 medium-sized marginal bristles; three longer marginal bristles; 

 several smaller bristles laterally near apex and on anterior (dorsal) 

 margin on semimembranous portion ; and some small lateral bristles. 

 Aedeagus (fig. 117).— Aedeagal end chamber exceptionally long 

 and broad. Lateral lobes (L.L.) with a conspicuous apical and dorso- 

 apical roughly triangular, dense patch of microverrucae or large 

 spicules. Median dorsal lobe (M.D.L.) relatively well sclerotized. 

 Accessory lateral lobe {A.L.L.) acuminate. Distolateral lobes 

 (DL.L.) very large, with an apical lateral, more heavily sclerotized 

 portion ; central thickening (C.TH.) conspicuous. Fulcrum extending 

 from S.I.T. to DL.L., long and narrow. Crochets (CR.) somewhat 

 reduced, shaped like a spearhead ; not as long as inner tube. Sclero- 

 tized inner tube (S.LT.) bearing a very conspicuous huge keellike 

 lateral sclerotization (L.S.L). Armature of inner tube (A.LT.) con- 

 sisting of a thick, median, dorsal spur. 



Fma/^.— Posterior margin of seventh sternum (fig. 75) with a 

 dorsal lobe which may be extremely small and triangular or much 

 longer with narrowly rounded apex; below this gently convex to 

 ventral margin. Row of five or six short bristles on eighth tergum, 

 above spiracle. Anal stylet (fig. 77) about si times as long as broad, 

 bearing one long apical bristle and two or three shorter ventromarginal 

 bristles. Head of spermatheca (fig,- 75, SP.) two times as wide as tail ; 

 tail about as long as head. 



Length.— Male, 2.2-2.8 mm. ; female, 2.9-3.3 mm. 

 Holotype.— Male, from Mustela sp., "Blackfalls" [Blackfalds], 

 Alberta. 



Records of Specimens Examined 



Canada Alberta (Mustela erminea) ; Labrador {Microtus pennsylvanicus, 

 Clethrionomys gapperi proteus) ; Keewatin, Northwest Territories (Microtus 

 pennsylvanicus); Ontario (Microtus sp., M. p. pennsylvanicus, Mustela c. 

 cicognanii) ; Quebec (Microtus pennsylvanicus labradonus, M. pennsylvanicus. 

 Clethrionomys gapperi proteus). 



United States. Maine : Penobscot County, "mink." Maryland : Montgomery 

 County (Microtus sp.) ; Prince Georges County (Peromyscus sp.). New Hamp- 

 shire: Carroll County (Microtus pennsylvanicus pennsylvanicus). Virginia: 

 Fairfax County (Microtus sp.). Wisconsin: Bayfield County (Microtus sp.). 



