EXPERIMENTS WITH THE DAISY ORGANISM. 29 



Result. — August 27, 1907: All the inoculated plants had galls. 

 The checks were free. 



September 30, 1907: All the inoculated plants were dead. The 

 checks were alive. 



The disease sometimes occurs naturally on this species. One such 

 plant has been observed bearing 6 galls. 



DAISY ON PYRETHRUM. 



Inoculations of September 20, 1907 (Brown). 



Seven full-grown plants of pyrethrum {Chrysanthemum coccineum) 

 were inoculated by needle pricks on the stems with agar streak cul- 

 tures 2 days old. The stems were woody and had almost ceased 

 growing. 



Result. — October 21, 1907: Small knots had formed on all of the 

 inoculated stems. The 3 check plants were free from knots. 



DAISY ON ENGLISH DAISY. 



Inoculations of August 1, 1907 (Brown). 



Eight seedling plants of the English daisy (Bellis perennis) were 

 inoculated by needle pricks with agar streak cultures 2 days old. 

 The stems were inoculated just below the surface of the ground. 



Result. — August 27, 1907: Five of the inoculated plants bore knots; 

 the two checks had no knots. 



DAISY ON SALSIFY. 



Inoculations op March 2, 1907 (Townsend). 



Twelve plants of Tragopogon porrifolius were inoculated near the 

 crown, using agar streak cultures of the daisy-gall organism made 

 February 27. Six controls were made at the same time on other 

 plants in the same relative positions. 



Result. — No galls formed on either the inoculated or the control 

 plants. In all probability these were the cultures used successfully 

 on carnation of same date. 



Inoculations of February 27, 1908 (Townsend). 



Dr. Townsend made a second set of inoculations on salsify with 

 positive results (PI. XXII, fig. A), but the notes concerning this 

 series have been misplaced. We do not know how many plants 

 were inoculated. The one shown in the illustration was removed 

 and put into alcohol May 8, 1908. 



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