1916} 



PARASITIC KHIZOCTONTAS IN AMERICA 



327 



In 1903 Sol by 104 reported the presence of a rosette disease of let- 

 tuce, which he described as follows: "The plants affected showed, 

 usually not long after transplanting, but occasionally at other stages, 

 a failure to send out central leaves freely. The leaf -bearing axis re- 

 mained shortened, and the last leaves formed remained short, making 

 a very striking contrast to the remainder of the plants in the bed 

 and to the lower leaves of the same plant. (Frequently the plants 

 overcome this tendency and make a fair amount of product with 

 longer time.) Examination of the roots showed areas occupied by 

 the hyphae of Ehizoctonia. ' ' In 1906 Selby 106 treated at length the 

 control of rosette in lettuce due to Rhizoctonia. 



- 14 DAMPIXO-OFF OF LAVATERA SEEDI.INCS P.Y I!Iti:octoHui 



(Experiment 9) 



