11 



flesh to turn brown, the cells becoming corky and hard, and they 

 were filled with a large quantity of starch (Plate I, Fig. 6). 

 Starch was not present to such an extent in the healthy cells (Fig. 

 7), The fungus appeared to be present only in the brown areas. 

 In the very early stages no infected cells were seen, but from 

 such spots Alt ernaria was isolated. The depth of the diseased 

 tissue varied with the degree of darkness of the epidermis. This 

 t.ls8ue was slightly bitter to the taste, and hard to chew as com- 

 pared with the healthy flesh. 



The mycelium of the fungus can plainly be seen in the 

 cells of the infected tissue (Plate I, Fig. 6). Under the very 

 dark portions of the skin the mycelium was abundant, while under 

 the lighter colored areas it was more difficult to find. Under 

 the reddest portion of the skin radiating froci the spot, none was 

 apparent, and no culture was produced from this region. 



Method s of Culture 



In isolating the fungus from the apples all possible 



precautions were taken in order to avoid contaminations. Except 



where otherwise specified the medium used for all cultures was 



cornmeal agar made according to the following formula: 



Cornmeal 50 gms. 



Water 1 liter 



Agar 1.5 i 



This was thoroughly sterilized in the autoclave for one-half hour 



at fifteen pounds pressure. The tubes and dishes were 



