Sys tern . C : 2 



8. Tail tip frequently clavate, one or two ovaries, distance from 

 anterior end to center of median oesopha,";eal bulb equal to, or 

 greater than distance from center of bulb to base of ogsophafjus. 

 ''-'silenchus 



Tail tin usually pointed, often curved ventrally. Distance from 

 anterior end to middle of median oesophageal bulb less than dis- 

 tance from this point to base of oesophagus. One ovary Tylenchus 



9. With one ovary 1*^- 



With two ovaries IS- 



10. Body more or less sausage-shaped, i.e., short and stout (a= 6-10), 

 length seldom more than about 0.6mm 11. 



Body slender (a= 20 or more), length usually more than 0.6mm 13. 



11. Body with prominent retrorse (directed posteriorlj^ annules, 

 usually longer than 0.3mm, a- 10 or more. Found in soil 12. 



Body without prominent annules, very stout (a= 6-8). Length 



about 0.3mjfii. Found iix roots Cacopaurus 



12. Annules with prominent spines or scales Griconema 



Annules of mature female without spines or scales Criconemoides 



13. :Hature female more than 2mm, often 3-5mm long. Found in galls 



in leaves, or in inflorescence of grains and grasses Anguina 



Body length less than 2mm. Fcamd in soil, or in roots and 



tubers; sometimes in bulbs, lesaves and stems lU. 



lU. Stylet longer than 3 times width of lip region 15. 



Stylet shorter or about twice width of lip region 16. 



15. Posterior portion of body strongly curved ventually Paratylenchus 



Body usually nearly straight, usually covered by loose cuticle 



of fourth molt Hemicycliophora 



