154 



progressed, the affected portion assumed a darker color, followed by a 

 gradual depression of the infected tissue, resembling in many cases that 

 caused by the black rot Macrosporium solani (see Fig. I), but without 

 any fruiting hyphae growing on the surface of the epidermis. It rarely 

 wholly destroyed the fruit, but as a rule seemed to hasten its maturity. 

 Generally the disease attacked the apical portion of the fruit; in a few- 

 instances, however, the central or basal portions would show the charac- 

 teristic M^atery discoloration. 



Fig. 2. Original condition of the fruit prior to infection. 



Fig. 3. Changed condition of fruit "b" due to infection. 



A microscopical examination of diseased portions of the fruit gave no 

 evidence of the presence of any parasitic fungus. The presence of a motile 

 bacillus seemed, however, to be fairly constant in "all tissue examined. 



Isolation of the genu.— In the isolation of the germ two different meth- 

 ods were employed. In one sections of the diseased tissue were removed 

 fi'om the fruit with a flamed knife and transferred to bouillon tubes, from 

 which loop plate cultures were made in agar. In the other method direct 



