Manchester Memoirs, Vol. Ivii. (1913), A^^. 11. 5 



on the upper and lower surfaces in the ratio of 4 to 7. 

 Since, however, the sporidial germ tube penetrates the 

 epidermal wall directly, and does not enter through the 

 stoma, the fact that the majority of the pustules appear 

 on the lower surface is not to be directly explained by 

 the greater abundance of stomata there. Inoculation 



■H i! 



^■fs"- phi. L^b 



Text-fig. 3. L.S. portion of stem, showing small mature 

 pustule .fj and two subsidiary pustules j,_, and j,. 

 Description in text. x 20. 



experiments showed that even when the sporidia were 

 sown on the upper surface of the leaf most of the sori 

 resulting were on the lower surface. The general distri- 

 bution of the fungus in relation to the tissues of the leaf 

 is shown in Text-fir. 4B. The young teleutospore sorus 



