New York Agricultural Experiment Station. 113 



As has been stated the rot always appeared to start in an apple 

 through a rupture in the epidermis caused by scab. It was 

 desirable to know if the fungus could penetrate the unbroken epi- 

 dermis and cause the rot. To determine this, artificial inocula- 

 tions were made with the same care and under the same sterile 

 conditions as previously described. Two apples of the same 

 variety were placed in a moist chamber ; a bit of the fungus from 

 a pure culture was placed upon one without puncturing or injur- 

 ing the epidermis in any way. The other fruit was inoculated by 

 puncture as previously described. The rot did not develop in 

 any of the fruits inoculated ort unbroken epidermis, though a 

 large surface growth of the fungus appeared, but on all the fruits 

 inoculated through a puncture the rot was produced. 



Table II. — Inoculations Made on Sound EpmERMis and 

 Through a Puncture. 



The results prove that the fungus is a wound parasite, as the 

 mycelium is entirely unable to penetrate the unbroken epidermis 

 and produce the rot. 



That the rot produced by the artificial inoculations was caused 

 by the fungus with which they were made, Hypochnus sp., was 

 definitely determined by a microscopic examination, or by making 

 cultures from some of the alTected tissue removed under sterile 

 conditions. In most of the examinations both methods were used. 

 In all but two or three cultures the fungus grew absolutely pure. 



