96 THE ROYAL SOCIETY OF CANADA 



In 14 days time the heart of the vegetable had rotted to a con- 

 siderable extent, while the effect on the stem had been such that 

 several leaves had died and fallen off, as shown in Fig. 11. 



While we anticipate a continuance of these inoculation trials in 

 growing plants, as the different varieties are available in season, we 

 recognise that the practical application centres around the effect on 

 the soil after a crop of turnips infected with this disease has been dis- 

 posed of. 



In view of this, as a preliminary trial, we prepared a series of pots 

 with soil, and sterilized them in steam under pressure for three hours. 

 A strong culture of the organism was grown in beef bouillon, and, the 

 maximum growth having been obtained, we mixed with the culture 

 a proportionate amount of a synthetic medium — Uschinsky's. 



With this mixture the soil in one series of pots was treated. 



The soil in the control series of pots was treated with a mixture 

 of sterile beef bouillon and Uschinsky's medium. 



In each of the pots, control and contaminated, an equal number 

 of turnip seeds was carefully sown, and from that time onward the 

 whole of the series watered with sterile water. 



In ten days time the plantlets were considered to have attained 

 a suitable size for demonstration, and they were accordingly photo- 

 graphed as shown in figure 15. 



Pots II and IV contained contaminated soil, Pots I and III being 

 the controls. 



There is sufficient evidence in the results of this preliminary trial 

 to warrant further investigation along these lines, particularly in view 

 of the economic importance of this phase of the question. 



Experiments with Fresh Vegetables. 



A large variety of fresh vegetables was cleaned, dried and then 

 cut with sterilised knives in slices of an average thickness of f-1 inch, 

 placed in sterilised Esmarch dishes and inoculated with one oese of 

 material from an agar culture. 



The results briefly noted are as follows: — 



Red Carrot. Softening and water-soaked appearance in 24 hours; 

 in a week, rotted through and centre quite black; a few days later, 

 rotting complete and slimy. 



White Carrot. In 24 hours softening beginning, with water- 

 soaked appearance; vascular circle brownish; action much the same 

 as on red carrot, except that the centre becomes dirty white and not 

 black. 



