434 First European Journey 



about modifications in nursery and orchard practice, and lead to a 

 rigid system of crop shipment inspection. ^^ Later when Smith 

 would prepare his text, Introduction to Bacterial Diseases of 

 Plants, several of the photographs used to illustrate the chapter 

 on " Crown Gall " would be taken from pure culture inoculations 

 made during these first years, 1906-1907.^* 



Smith did not present the discovery in 1907 before the Society 

 of American Bacteriologists. At one of the sessions of the Society's 

 meeting of December 29-31, 1908, however, he addressed the 

 Society on " The Etiology of Plant Tumors," illustrating his lecture 

 with a series of lantern slides, numerous stereopticon photographs 

 of inoculated plants of various species and of widely different 

 families. Science s ^^ abstract of the address reported that 



Hundreds of pure culture inoculations [had] been made. The organism 

 cultivated from the Paris daisy has been inoculated many times successfully 

 into the same and also into the peach, rose, hop, sugar-beet, white poplar 

 and other susceptible plants. That from the crown gall of the peach has 

 been many times successfully inoculated into the peach, and also into the 

 Paris daisy, sugar-beet, hop and other plants. The schizomycete from the 

 hop has been inoculated successfully into the hop and into the Paris daisy, 

 sugar-beet and other plants. One of the astonishing things about this 

 crown-gall organism is the number of families which are subject to infec- 

 tion ; in other words, the very simple and generalized nutritional needs of 

 the parasite. In some ways it resembles the root-tubercle organism of Legu- 

 minosae, but is not identical. It has been inoculated into clovers with the 

 production of knots. Quite recently from the hard gall of the apple 

 (selected by Dr. Hedgcock) we [Smith, Townsend, and Brown] have 

 isolated an organism which appears to be like that occurring in other crown 

 galls, and with this, hard galls have been produced upon the Paris daisy. 

 A similar if not identical organism has also been isolated from the hairy 

 root of the apple and successfully inoculated into the sugar-beet, i. e., with 

 the production of similar root-tufts at the point of inoculation. There is 

 now little doubt, therefore, that the hairy root of the apple is also of bac- 

 terial origin. 



Metastatic growths occur on these plants, but up to this time we have 

 not definitely determined the channels of infection from the primary tumor 

 to the secondary ones. These are easily discovered in the case of the olive- 



^^ Fifty years of pathology, op. cit., 32. 



" Op. cit., 413-432. 



^^N. s. 30(763): 223-224, Aug. 13, 1909- Abstracts of three other papers pre- 

 sented to the Society of American Bacteriologists by Smith also published were: Seed 

 corn as a means of disseminating Bacterium stewarti ; The occurrence of Bacterium 

 pruni in peach foliage; and Two sources of error in the determination of gas- 

 production by microorganisms. 



