NO. 4 FLEA GENUS PEROMYSCOPSYLLA — JOHNSON AND TRAUB 5 



3. Genal process hidden by upper genal spine (fig. 74) ; three dorso- 



submarginal bristles between spiniforms and antennal groove (fig. 74) ••4 

 Genal process visible above upper genal spine (fig. i, G.P.) ; two 

 dorsosubmarginal bristles between spiniforms and antennal groove 



(fig. I) ;••;•■■■; ^ 



4. Movable finger long, narrow, and crescentic (fig. 87, F.) ; lateral 



lobe of aedeagus (fig. 120, L.L.) with large, scalelike spicules 



bide^itata (Kolenati), p. 54 

 Movable finger more or less triangular (figs. 81, 82, 86, F.) ; lateral 

 lobe of aedeagus with small spicules (figs. 11 7-1 19, L.L.) 5 



5. Crochets (fig. 119, CR.) as long as, or longer than, sclerotized inner 



tube (S.LT.) ; eighth sternum (fig. 85) with long bristles sub- 

 marginal 



Crochets (fig. 117, CR.) not as long as sclerotized inner tube 

 (S.LT.) ; eighth sternum with long bristles obviously lateral, re- 

 moved from apex at least by length of the short apical bristles 



(fig. 76) 7 



6. Eighth sternum with ventral margin straight (fig. 85) 



ostsibirka longiloha (Jordan), p. 53 

 Eighth sternum with ventral margin concave (fig. 122, 8S.) 



ostsibirka ostsibirica (Skalon), p. 51 



7. Eighth sternum (fig. 76) with only two long bristles ; dorsal margin 



of movable finger (fig. 81, F.) markedly convex (North America, 



Rocky Mountain region) hamifer vigens (Jordan), p. 47 



Eighth sternum (fig. 78) with three or four long bristles; dorsal 



margin of movable finger (fig. 82, F.) straight or somewhat concave 8 



8. Four long bristles on eighth sternum (fig. 78) ; movable finger (fig. 



82, F.) with posterior margin markedly concave 



hamifer hamifer (Rothschild), p. 43 

 Three long bristles on eighth sternum (fig. 129) ; movable finger 

 (fig. 131, F.) with posterior margin straight 



hamifer cnneata new subspecies, p. 49 



9. Upper genal spine the longer (fig. 59) ^° 



Upper genal spine the shorter (fig. i) ^4 



ID. Preantennal area of head with six long bristles (discounting mar- 

 ginals and subdorsals) (fig. 55) ; eighth sternum broad, bearing 

 seven to nine long marginal bristles (fig. 53) • -scJcnis (Rothschild), p. 31 

 Preantennal area of head with five long bristles (discounting mar- 

 ginals and subdorsals) (fig. i); eighth sternum with no more 

 than two long submarginal bristles (figs. 61, 66, 69, 71) ii 



11. Postantennal area of head with rows of bristles irregular (fig. i) ; 



apex of eighth sternum rounded (fig. 61); distolateral lobe of 

 aedeagus (fig. 112, DL.L.) very large, three-fourths length of end 



chamber; lateral lobe {L.L.) reduced caiatina (Jordan), p. 34 



Postantennal area of head with four regular rows of bristles (fig. 

 74) ; apex of eighth sternum (fig. 66) truncate ; distolateral lobe 

 of aedeagus (fig. 113, DL.L.) small, one-third length of end 

 chamber ; lateral lobes (L.L.) normal, not reduced 12 



12. Movable finger rather narrowly expanded dorsocaudally ; without 



patch of small proximal bristles (fig. 64, F.) ; long bristles on 



