Apr., 1922! RAINES VEGETATIVE VIGOR OF THE HOST 2O3 



the case of wheat and rye. This may be regarded as further evidence, if 

 any be required, of the physiological distinction of the rubigo-vera forms 

 growing on wheat and rye on the one hand, and on barley and oats on 

 the other. 



Hungerford (1920, p. 270) reports an experiment testing the time of 

 first appearance of rust on wheat plants grown from rust-infected and from 

 clean seed, similarly indicating that the condition of the seed does not 

 affect the time of first appearance of the rust. 



