DESCllIPTION OF BAC'I^ERiUM 'rUMEFAClENS. 105 



March 31, 1909: Three more of the 7 beets had clusters of little 

 roots at the inoculated places. The checks showed the punctured 

 places healed; no hairs had formed. 



Inoculations of November 11, 1900 (Brown). 



Eight sugar beets were inoculated with G-day-old agar streak 

 cultures made from colonies plated from gall on apple root produced 

 by inoculation (p. 103) with culture of apple hairy-root organism 

 derived from the Whetzel tree. 



Result. — March 10, 1910: One beet was pulled and both galls and 

 hairy-root found present. 



April 7, 1910: The remaining 7 beets were pulled and typical 

 hairy-root found on all of them. Three liad both hairy-root and 

 galls, i. e. clusters of roots (hair3^-root) growing out of galls which 

 were not large (PI. XVII, fig. 3; PI. XIX, figs. 1 and 2). 



MISCELLANEOUS. 



In 1910 organisms were isolated from salsify gall, turnip gall, and 

 parsnip gall, and inoculated respectively into salsify, turnip, and 

 parsnips, and each also into sugar beet, but all of the inoculations 

 were neg-ative. 



^t^' 



DESCRIPTION OF BACTEEIUM TUMEFACIENS « FEOM DAISY. 

 MOPwPHOLOGICAL CHAHACTERS. 



Vegetative cells. — The daisy knot organism is a small schizomycete 

 of variable length, but usually short and generally not over 0.6 to l/x 

 in diameter, unless treated v>'ith severe flagella stains. None as 

 slender as 0.2 or 0.3 // have been observed. 



Taken directly from a gall and stained with gentian violet, the 

 following measurements were obtained in 1909: Single rods, 0.6 to 

 1.0/^ by 1.2 to 1.5/i; paired rods, O.G to 1.0/z by 2.4 to 2.8//. These 

 were obtained in the following way: The surface of a young gall 

 was scraped, washed, and sterilized; thin slices were then placed in 

 distilled sterile water on sterile slides and the bacteria allowed to 

 diffuse out of the sections for an hour. The sections were then 

 lifted with sterile forceps, the fluid dried and stained. Only scat- 

 termg rods were visible. 



"WTicn grown on agar for two days and stained with Loefller's 

 flagella stain (in 1907) its length was 2.5 to 3/« and its breadth 0.7 to 

 0.8/t, or occasionally a little wider. Some recorded as 6// long were 

 probably paired rotls. 



a Name first used in Science, n. s., vol. 2.5, April 'Ai, 19u7, p. (172. 

 213 



