New York Agricultural Experiment Station. 839 



ease, while Maiden Blush, even in a most unfavorable season, has 

 comparatively little of the disease. In 1894, as shown in Table 

 VII, the average injury by scab to the fruit of six Fall Pippin 

 trees was 68.2 per cent. An untreated Maiden Blush averaged 

 but 11.74 per cent. 



Mr. Paddock has recently examined for me a few varieties of 

 apples to see whether or not there are any structural differc^nces 

 in the epidermis and cuticle of scab resistant varieties like Ben 

 Davis, G'rimes Grolden and Talman Sweet as compared with sus- 

 ceptible varieties like Fameuse, Esopus Spitzenburg and Rhode 

 Island Greening. So far as he has made examiuation the resis- 

 tant varieties have thicker cuticle and thicker walled epidermal 

 cells. This, if it holds true generally, means that the power to 

 resist attacks of the scab fungus is correlated with structural 

 peculiarities and it is quite reasonable to suppose that these scab- 

 resistant characteristics may be intensified by breeding and se- 

 lection. Work in this direction has already been undertaken 

 with the orange by Mr. H. J. Webber of the Division of Vege- 

 table Pathology, United States Department of Agricultui*e, in 

 connection with his work for the Division in Florida. He writes 

 under date of January 7, 1898: "In the case of the orange we 

 have found very marked differences in the resistance of certain 

 varieties to disease; for instance, foot rot, the most serious dis- 

 ease with which orange growers have to contend, is controller! 

 mainly by grafting or budding the varieties desired on sour or- 

 ange stock, which is practically immune from the disease. Again, 

 the sour and bitter-sweet oranges are practicaUy immune to 

 blight, which is also one of the very serious diseases. 



" It is not alone fungous diseases, however, that may be treated 

 in this way. The orange rust, which is caused by a surface-feed- 

 ing Phytops, I feel confident could also be controlled by breeding 

 resistant sorts." 



This line of work which Mr. Webber has undertaken in Florida, 

 namely, the breeding of varieties resistant to the attacks of cer- 

 tain insects and diseases, if followed in connection with some of 

 the cultivated fruits of this region might be productive of resuKa 



