ROOT-KNOT DISEASE OF TOMATOS. 



51 



10. That an alkaline substance like caustic soda does not in any 

 way check the disease. 



11. That nitric acid (as representing mineral acids) is on the 

 right lines but very costly. 



12. That copper sulphate has no appreciable adverse effect on 

 tomato eelworms in soil. ^ 



13. That poisonous substances like sodium cyanide, mercury 

 chloride, and copper sulphate may be introduced into the subsoil 

 in certain quantities without endangering the growing crop. 



