3it. 



, . Detenninati on of viability of Heterodera larvae by 

 direct obi^I^ation of lar vae released from tne egg m echan- 

 xcaiiy^ STAiaL AND (i^^t) fauna that if larvae were relea sed 

 from well soaked eggs by cutting the egg membrane with a 

 fine knife the shape of the larva after leaving the egg was 

 a good indication of whether it was alive or dead. The method 

 deserves attention for those cases where hatching tests are 

 too troublesome or impossible because of absence of stimu- 

 lating substances. 



