NEMATODE PARASITES OF BIRDS 51 



Preanal sucker 80 to 90/* in diameter; righl spicule 2.3 nun., long; female 

 T ! to 9.6 nun. long; eggs T."i to 78m long by 43 to 48/* wide. 



Heterakis longecaudata, p. 66. 



10. Preanal sucker 250/* in diameter: cluneal aperture I.;', mm. from posterior 



extremity; female 9.5 mm. long; anus 1.5 mm. from posterior extremity. 



Heterakis bosia, p. 57. 



Preanal sucker not over 124/* in diameter: cloaca] aperture not over 488/t 



from posterior extremity: female 7 to 8 mm. long; anus not more than 



1 mm. from posterior extremity 11. 



11. Preanal sucker 83/* internal diameter, 124/* external diameter; 5 pairs of 



preanal papillae and 1 pair of very large adanal papillae: length of caudal 

 appendage of male less than distance of cloacal aperture from most 



posterior papillae Heterakis bonasae, p. 75. 



Preanal sucker only 36/* in diameter; 3 pairs of preanal and 1 pair of small 

 ventral adanal papillae: caudal appendage almost twice as long as dis- 

 tance from Cloacal aperture to most posterior papillae. 



Heterakis fariai, p. 63. 



12. Short spicule 150/* long; female 5.1 mm. long; its anus 540/* from posterior 



end: vulva at about posterior third of body, dividing body length in ratio 



of 12 : 5 Heterakis pusilla, p. 70. 



Short spicule 260/* long; female 8.2 mm. long, its anus 830/* from posterior 

 end ; vulva slightly anterior to middle of body. 



Heterakis putaustralis, p. 71- 



13. Spicules over 1 mm. long 14. 



Spicules less than 1 mm. long 17. 



14. Male 14 to 22 mm. long: female 22 to 31 mm. long; eggs 52/* by 29/*; 



according to figure, spicules over 2 mm. long Heterakis arquata, p. 55. 



Male not over 9 mm. long; female not over 12 mm. long; eggs 70,<* or more 

 by 42/* or more: spicules not. over 1.8 mm. long 15. 



15. Head with 3 lips and .''. small interlabia ; no papillae described in vulvar 



region : spicules about 1.25 mm. long Heterakis interlabiata, p. 64. 



Head with 3 lips but no interlabia: vulvar region with variable number 

 of papillae; spicules equal or subequal, 1.4 to 1.8 mm. long 16. 



16. Lateral alae extend only along esophageal region of body ; male 7.5 to 9 



mm. long, its tail 1/13 of total length; female 9 to 12 mm. long, its tail 



1/7.3 of total length Heterakis isolonche, p. 64. 



Lateral alae extend almost the whole body length; male 15 nun. long, its 

 tail 1/23 of total length; female 17 mm. long, its tail 1/14 of total length. 



Heterakis neoplastica, p. 65. 



17. Spicules over 600/* long 18. 



Spicules not over 500« lout; 23. 



18. Male 4 mm. long; female 4.2 nun. long Heterakis nattereri, p. 75. 



Male 9 mm. or longer; female 14 mm. or longer 19. 



19. Preanal sucker 290/* in diameter; the most anterior pair of preanal caudal 



papillae very small and situated a considerable distance anterior to the 



sucker; spicules at least 890/* long Heterakis tenuicauda, p. 7.'!. 



Preanal sucker not over 230/* in diameter; the most anterior preanal 

 papillae not situated as above: spicules not over 860/t long 20. 



20. Length of females 25 mm. or more, the tail short (anus not over 4<!0/* from 



po&terior end) 21. 



Females not over 15 mm. long, the tail comparatively long (anus 800/* or 

 farther from posterior end) 22. 



