100 CKOWN-GALL OF PLANTS. 



Inoculations op December 4, 1908 (Brown). 



Eight young sugar beets were inoculated with subcultures 2 days 

 old from apple-gall colonies. These were descended from the same 

 poured-plate colonies (second D. C.) used for the tomato inoculations 

 of this date (p. 97) . The beets were in a cool house making a slow 

 growth. 



Result. — December 18, 1908: Galls formed on only 2 of the beets 

 and these were not more than half an inch in diameter. The beets 

 had not grown much since the time of inoculation. 



Inoculations op June 24, 1910 (Brown). 



This is the culture recorded under ''Morpholog}^" as ''old apple" 

 and now believed to be something other than the crown-gall organism. 

 Ten beets were inoculated on the roots by needle pricks from a 3^oung 

 culture. 



Result. — July 18, 1910: All negative. 



HARD GALL OF APPLE ON MONSTERA. 



Inoculations of November 12, 1908 (Smith). 



Six root tips (aerial roots) of Monstera deliciosa were inoculated 

 from colonies on plates poured November 4 from Hedgcock's hard 

 gall of the apple (first Iowa). When used for inoculation these 

 colonies were white, dense, fleshy, circular, wet-shining. 



Result. — No galls. Some of the roots bifurcated owing to injury 

 of the growing point. 



RELATION OF CKOWN-GALL TO HAIRY-ROOT. 



HAIRY-ROOT OF APPLE DUE TO BACTERIA. 



Originally we had no intention to touch the subject of hairy-root, 

 but Doctor Hedgcock having expressed a belief that it was not due 

 to any organism and having sent on material with the request that 

 we examine it, plates were poured and inoculations were made with 

 the following results: 



On November 7, 1908, an apple tree with small roots in clusters 

 on the main root was sent in from Iowa bv Doctor Hedgcock to 

 Doctor Smith to experiment with for isolation of the hypothetical 

 organism whicli we believed to exist therein and he did not. There 

 was no typical gall on either roots or stem, but there were small 

 enlargements at the base of the little clusters of hairy roots. A few 

 of the rootlets of the bunched mass were rather llesh3\ The root- 



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