MICHIGAN ACADEMY OF SCIENCE. 75 



asci; and only about half of the asci seem capable of producing spores. The 

 other half remain similar to that shown in II b. 



From inoculation experiments with the conidia it would seem as though 

 they were not very active as infecting agents. From thirty inoculations 

 with conidia not a single infection developed; but from the same number 

 of inoculations with ascospores, four succeeded. The attempts to inoculate 

 with conidia was made in September, and with ascospores in May. The second 

 5'ear after these attempts were made the whole plum orchard was uprooted, 

 so these experiments were terminated more suddenly than was anticipated. 

 At all events it seems tolerably clear that in any case, whether by conidia or 

 by ascospores, infection is not easy to accomplish. Only two methods wei'e 

 employed, one by puncturing the living cortex with a needle and inserting 

 some spores, and the other by placing spore material into the crevices, in 

 and around the bud, then placing a few drops of water in connection with the 

 inoculating material. 



