1015.] Qi 



18. Head of receptacuhim seminis shorter than tail and less 



than twice as long as it is broad (fig-. 18) rotJischildi 



Head of receptaculum seminis longer than the tail and at 

 least twice as long as it is broad 19 



19. A large mimber of bristles on eighth tergite below stigma ; 



sensory plate much shorter than its distance from base 



of stylet hirundinis 



Less than 12 bristles on eighth tergite below stigma ; sensory 

 plate as long as its distance from stylet 20 



20. Head and tail of receptacvdnm seminis almost equal in 



length (figs. 28, 30) 21 



Head of receptaculum seminis about twice as long as tail 

 (figs. 32, 36, 38) 22 



21. Stylet more than twice as long as it is broad columbae 



Stylet less than twice as long as it is broad garei 



22. Pale brown; second segment of midtarsus without bristles 



on the basal half of the ventral surface .fringillae 



Very dark bi'own, almost black ; second midtarsal segment 

 with two or three bristles on the basal half of the 

 ventral surface 23 



23. Hindfemur on inner surface with a lateral row of four to 



six bristles ; apex of seventh sternite in a lateral view 

 almost evenly rounded (fig. 36) gallinae 



Hindfemur on inner surface with a lateral row of seven or 

 more bristles ; apex of seventh sternite almost truncate 

 or slanting (fig. 32) vagabunda 



24. Mammal fleas. — Forefemur with one or no bristles on lateral 



surface metis 



Forefemur with several bristles on lateral surface 25 



25. Occiput with one bristle above centre of antennal groove ... 26 

 Occiput with two or more median bristles 27 



26. (^ : Finger with two stout bristles, upper one much nearer 



to lower bristle than to apex (fig. 45). ?: Seventh 

 sternite deeply sinuate ventrally (fig. 46) londiniensis 



