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ocular examination will fail to discern any symptoms until the root is pulled or 

 lifted. 



This condition, produced and noted experimentally, is quite usual in the 

 field, and is shown well by Fig. 12. 



In both these trials the control plants which had been pierced with a sterile 

 needle did not show any sign of disease. The specimens obtained experimentally, 

 in addition to roots which had become naturally infected in the field have been 

 successfully preserved for museum purposes in a 10 per cent, solution of 40 per 

 cent, formaldehyde. 



7. — Healty Turnip plant. 



At a later date, further trials were made with growing plants, inoculations 

 being made from young agar cultures of the organism reisolated from the artifi- 

 cially produced disease described immediately above. 



Fig. 7 is a photograph of one of the healthy turnip plants with which these 

 trials were carried out. Inoculations were made in the crown of the turnip, 

 caused a rapid production of the disease, and in five days the condition as shown 

 in Fig. 8 was obtained. 



The leaves had drooped and withered to such an extent that they hung over 

 the side of the pot, and the root was so badly rotted that it could not be lifted 

 out of the soil. 



Fig. 9 represents a turnip which had been inoculated on the same day as the 

 one just described. In this case the inoculation was made by needle puncture in 

 the root, and twelve days later when the iphotograph was taken the leaves were all 

 withered and partially rotted, while the root was completely rotten. 



Fig. 13 is a photograph of a turnip which had been inoculated by needle 



