20 



amount of asparagin was in the synthetic medium used the spores 

 and mycelium warre abundant. In media with double the amount of 

 glucose the growth of mycelium was large, but that of spores few. 

 On synthetic media without asparagin the culture was weak and 

 spread over a large surface. The same was true when no glucose 

 was present. In the last two media the spores, when produced, were 

 in a few large, apparently normal clusters instead of in many 

 small ones distributed over the colony. On plain agar the devel- 

 opment was weak and growth ceased entirely after the colony reached 

 a size of about 2 cm. 



Ino.culat ion 



When inoculated on healthy apples the fungus produced a 

 characteristic spot. The development was slow. About two weeks 

 time was necessary to show any distinct spot. In many cases no 

 infection took place. The spot when produced was light brown with 

 a distinct margin which was slightly darker than the rest of the 

 diseased portion. After about a month the spot was sunken and had 

 not developed over 1 cm. in diameter. The surface was slightly 

 hardened . 



In cross section the spot showed in many cases a diseased 

 portion of much larger area than could be seen superficially. The 

 fungus had, in one case for example, penetrated almost into the 

 core of the apple in three weeks. It made a rather soft, spongy 

 rot - not as soft, however, as that of Penicilliura. While the 

 surface spot in this case was only .5 cm. in diameter, the tissue 

 below was rotted 2 cm. deep and 1 cm. in either direction from 

 the spot. In other cases the rot was not so rapid - penetrating 



