60 HATCH EXPERIMENT STATION. [Jan. 



manner of growth in gelatine proved it to be of an angerohic * 

 nature. From time to time the oro-anism was transferred to 

 fresh gelatine ; and daring the next fall three varieties of straw- 

 berry plants, including the Marshall, Belmont and Sharpless, 

 were transplanted to the greenhouse. After the new plants, 

 which were not especially robust, had made some growth, 

 they were placed in a warm, humid atmosphere, and the 

 roots of a number of plants of each variety were inoculated 

 with the pure cultures of bacteria from the gelatine tubes. As 

 a result of the inoculation, the plants after a few days showed 

 the eftects of the disease, some, however, more than others; 

 but in all cases the disease was somewhat milder than in the 

 plants originally affected. An examination of the affected 

 parts of the plant showed the same bacterium, and cultures 

 made from the petioles and roots gave the same character- 

 istic micrococci. Other strawberry plants were again in- 

 oculated with the new isolated forms, with corresponding 

 results. 



No further experiments in this direction were considered 

 necessary, inasmuch as the effects of the bacteria upon the 

 plants had been ascertained. I will state here, however, 

 that I had never seen the disease previous to this, neither 

 have I been able to detect it since. I consider it one of 

 those sporadic afflictions with which any plant is likely to 

 be troubled, provided just the right conditions are at hand. 

 In this instance the conditions of the weather and that of the 

 plant were especially ^ivorable for such an attack. All of 

 the plants under examination were young, and had not been 

 transplanted a great while ; and, furthermore, they had all 

 the appearances of plants which had not become firmly estab- 

 lished in the soil. The organism is, not unlikely, a com- 

 mon form of micrococcus which under peculiar conditions is 

 liable to cause some injury. Inasmuch as the primary cause 

 of the disease has its origin in a weakened condition of the 

 plant, and inasmuch as there is every reason to believe that 

 the organism gains its entrance through the root, any attem[)t 

 to apply fungicides would l)e useless. The only practical 

 method of dealing with a difficulty of this kind, should it 

 occasionally make its appearance, is to take more pains in 



* Not requiring free oxygen. 



