151 



nore in diameter have been found infected, apparently irrespec- 

 ■■•- »<- *Wr size or position. So far as field observations show, 

 s might enter wherever a spore happened to find a rest- 

 ng place. All of my experiments, however, have failed to intro- 

 duce the fungus into a branch while the thin brown layer of 

 :ortex remained intact ; though it readily entered when this was 

 scraped off or punctured. As the fungus does not attack the 

 'es, I was not surprised when repeated attempts failed to 

 .se into green twigs, where, although no cortex 

 nt, the quality of the food and the character of the bark 



ive of thei 

 :he fungu; 



ntroduce the disi 



s evidently not suited to its development. The present suppo- 

 sition is, therefore, that infection takes place only through wounds ; 

 sr, possibly, through the lenticels. 



Wounds are, unfortunately, only too frequent, especially in the 

 :ase of a tender, rapidly-growing tree like the chestnut, which 



