EXPERIMENT STATION REPORT. 367 



Ferric oxide, 0.5213 



Calcium oxide, 54.5136 



Magnesium oxide, 7 5788 



Potassium oxide, 26.0129 



Pliosphoric acid, 11.3732 



The differences in the composition of Ashes I. and II. are 

 in the same direction as noticed in the ashes of healthy and 

 diseased fruits, of the same variety of peaches. 



Prof. Peuhallow's microscopic observations are stated by 

 him in the following summary : — 



1. Healthy wood shows comparatively little stored starch ; 

 but fungous growth is present in the outer layers of the bark. 



2. Diseased wood shows an abnormally small develop- 

 ment of the cells, and the invariable presence of large quan- 

 tities of starch ; also an abundance of fungous growth. 



3. Diseased leaves show the presence of fungous growth, 

 discoloration and cells filled with starch. 



4. The fungus appears first on the surface of the trunk 

 or branches, and thence enters the woody structure, when 

 the conditions are favorable. 



5. There is little or no difference between the tissues and 

 cell contents before and after the leaves fall. 



6. While fungus is abundant on fully diseased trees, it is 

 also to be found on trees which, once diseased, had been 

 restored to a condition of vigorous health.* 



These results apparently confirm the views entertained 

 when planning the investigation, and tend to show that an 

 interior disorder, caused by an abnormal composition of the 

 sap — as far as its mineral constituents are concerned — pre- 

 cedes the serious development of the fungus. 



Our late advice to fruit-growers has been based on the 

 teachings of the experiments previously described. 



We recommend a careful watching of the peach orchard, 

 to notice the disease in its first stages if possible. 



The first signs are to be met by an immediate application 

 of from two to three pounds of muriate of potash to each 



* More detailed investigations of Prof. Penhallow have been recently published 

 by him, in connection with the publications of Houghton Farm. 



