13 (11) Penis papilla with terminal lobe, ejaculatory duct opening 



on ventral side of papilla .... Phagoaata crenophila (p. 39) 

 Penis papilla without terminal lobe, ejaculatory duct 



opening at tip of papilla 14 



14 (13) Penis rudimentary, without bulb and with small papilla: 



Hymanelta retenuovaip. 31) 

 Penis well-developed, with bulb and papilla 15 



15 (14) Ejaculatory duct with blind diverticulum: 



Phagoaata velata (p. 35) 

 Ejaculatory duct without diverticulum 16 



16 (15) Copulatory bursa rounded, sac-shaped 17 



Copulatory bursa U-shaped, testes in part longitudinally 



fused Phagoaata vemalis (p . 34) 



17 (16) Penis with round bulb and narrow ejaculatory duct: 



Phagoaata bulbosa (p. 36) 

 Penis with small bulb and wide undivided penial lumen: 



Phagoaata monopharyngea (p. 33) 



18 (10) Penis papilla long, conical, with fibrous layer below outer 



epithelium, penis lumen with two seminal vesicles: 



Phagoaata graailis (p. 43) 

 Penis papilla short, truncate, with intermingled circular 

 and longitudinal muscle fibers below outer epithelium, 

 penis lumen not subdivided .... Phagoaata woodworthi (p. 44) 



19 (9) Bursa duct with anterior glandular and posterior non-glan- 



dular sections 20 



Bursa duct non-glandular throughout: 



Potyoelis aoronata boreatis (p. 27) 



20 (19) Penis papilla as large as, or larger than, penis bulb: 



Polyaelis aoronata aoronata (p. 25) 

 Penis papilla smaller than penis bulb: 



Polyaelis aoronata brevipenis (p. 26) 



21 (8) Head with slender, pointed auricles: 



Phagoaata bur sap erf or at a (p. 37) 

 Head without pointed auricles 22 



22 (21) Polypharyngeal Phagoaata graailis (p. 43) 



Monopharyngeal 23 



23 (22) Eyes normally two (smaller accessory eye spots may occur) . . 24 



Eyes wanting Proaotyla typhlops (p. 64) 



Eyes many, in two longitudinal rows: 



Phagoaata morgani polyaelis (p. 41) 



16 



