8 



An examination of the fungus showed it to be a species of Fusa- 

 rium. Spores were produced abundantly and proved to be the 

 characteristic Fusarium type — club-shaped in the young stage ; more 

 or less elliptical when mature ; usually four-celled, varying to six; 

 size varies from 32 — 38.4 fi in length, and the conidiophores are 

 short and thick. (See Fig. 3.) In none of the rot examined was 

 there the slightest trace of any other fungus. 



Pure cultures of the Fusarium were obtained on stewed tomatoes, 

 and these were used to inoculate green fruit. Inoculations were 

 tried both around the style without penetrating the epidermis, and 

 through a wound. The Fusarium placed around the style did not 

 take effect, except in one case in which a small, quite characteristic 

 spot was obtained in this way on the green fruit. 



Fig. 2. Mycelium from infected cells pene- Fig. 3. Conidia of Fusarium. 



trating healthy tissue. 



Inoculations through punctures in the epidermis grew with varying 

 vigor. When deep punctures were made the mycelium grew rapidly 

 until nearly the whole fruit became involved. The tissues affected 

 were softer, more collapsed and lighter in color than in the case of 

 natural infection, as was to be expected from the vigor of the growth. 

 Here, also, the tissues were perfectly dry. The surface of the rot 

 became covered with white concentric rings. The mycelium in this 

 case permeated the tissues in all directions, especially in strands be- 

 tween the cells. Spores were produced throughout, especially in 

 the intercellular spaces, (See Fig. 4.) The concentric rings proved 

 to be spore clusters developed in dense, conical tufts on the surface. 

 (See Fig. 5.) Macroconidia have not been observed in connection 



