26 CEO WN -GALL OF PLANTS. 



Inoculations of January 8, 1907 (Brown). 



Inoculated S plants with organism plated December 18 and 

 designated as B. 



Result. — In 7 days galls had started to form on each plant at the 

 place inoculated. 



Inoculations of January 18, 1907 (Brown). 



Inoculated 7 old plants on both old and young stems — 24 inocu- 

 lations in all. Agar culture 49 days old (white organism). 



Result. — Februar}^ 6 : No galls had formed; cultures probably dead. 



Inoculations of February 6, 1907 (Brown). 



Inoculated 8 more old daisy plants on young twigs only with a 

 culture 9 days old. 



Result. — February 18, 1907: Small galls had formed. 



Other inoculations were made with the original cultures, as follows: 



December 13, 1906. — Eight daisy plants were inoculated vfith 

 cultures of the same date as those used November 27 and which had 

 produced galls. These cultures were now 19 days old. 



Result. — December 24: Galls were forming at inoculated places. 



December 31: All the inoculated plants had galls. On Febru- 

 ary 23, 1907, photographs were made (PI. I, fig. 1). 



Julv 10, 1907: The galls had reached a large size and were quite 

 hard (PI. I, fig. 2). 



December 21, 1906. — Eight inoculations and 4 checks. 



Result. — December 31: Galls at all inoculated places; checks free; 

 organism plated out of one of these galls and identified. 



January 19, 1907. — Inoculated 7 plants with organism plated from 

 gall on December 31. 



Result. — Januar}" 30: Indications that galls will form. 



February 5 : Galls formed at each inoculated place. 



t 



Inoculations of February 18, 1907 (Smith). 



Four vigorous young plants of white-flowered Paris daisy and 6 

 similar plants of the yellow-flowered Paris daisy were selected. Each 

 plant of the white variety branched at the base into two equal shoots ; 

 7 of these shoots were inoculated and the eighth was held as a check. 

 On the inoculated shoots also check pricks were made an inch or two 

 above the places where the infected needle entered. All of the inocu- 

 lations were made by needle pricks, using a slant glycerin-agar cul- 

 ture, 7 days old, which had been streaked from another slant agar 

 culture. The organism was derived from a strain which had been 

 passed twice through the dais}'' by Miss Brown with the production 



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