XXVI LIST OF ILLUSTRATIONS 



Page 



321. Inoculated crown gall on sugar beets, showing necrosis 422 



322. Natural crown gall on willow limbs — from South Africa 423 



323. Tumor-strand in cross-section (in daisy stem near pith) — magnified. 



From an inoculated plant 424 



324. 1. Radial longitudinal section of leaf-trace of Paris daisy, showing 



the normal anatomy, pitted vessels at right; spirals at left. 2. 

 Radial longitudinal section of leaf-trace of inoculated Paris daisy, 

 showing the interpolation of a tumor-strand — magnified. 3. Tumor 

 strand in cross-section (stem of an inoculated Paris daisy), showing 

 large cells with big nuclei. 4. Cross-section of stem of an inoculated 

 Paris daisy with tumor-strand showing immature tracheids, develop- 

 ing therefrom 425 



325. Crown gall tumor-strand in corte.x of an inoculated Pelargonium 427 



326. Like figure 327, sub 4, but tumor full-grown and ruptured to surface 



of daisy leaf. Stem structure very distinct 428 



327. 1. Very early stage of crown gall on inoculated daisy stem. 2. Longi- 



tudinal section of unruptured small secondary tumor in petiole of an 

 inoculated daisy. 3. Part of sub 2 enlarged. 4. Cross-section showing 

 stem structure of secondary tumor in a daisy leaf — the tumor was 

 still developing 429 



328. Lignin out of place in crown gall, i.e., deposited on walls of 3 large 



parenchyma cells 430 



329. Vascularized crown gall in bark parenchyma of Paris daisy induced by 



shallow needle-prick inoculations 431 



330. Inoculated crown gall on white Paris daisy — showing a killed branch. 



Time, 7 months 432 



331. Nucleated cells of crown gall of daisy with bodies formerly identified 



as the bacteria in place. Gold chloride impregnation 433 



332. a, b. Crown gall on the daisy showing mitochondrial (?) rods formerly 



identified as Bacterium himefaciens within the cells. One rod branched 434 



333. Inoculated crown-gall teratoma on cauliflower, enlarged. Also side view 



natural size 435 



334. Inoculated crown-gall teratoma on Ricinus communis (castor oil plant). 



Plant badly dwarfed. Normal stem of same age at right 436 



335. Tobacco crown gall bearing flower buds as result of a pure culture 



inoculation of Bacterium tumefaciens 437 



336. A, B. Inoculated leafy crown galls on tobacco internodes 439 



337. Natural crown-gall witch-broom on Dianthus cnryophyllus (the car- 



nation) 440 



338. Inoculated crown-gall teratoma on hothouse geranivun (Pelargonium).. 442 



339. A, B. Sections of an internodal tobacco teratoma 443 



340. A, B. Inoculated tobacco crown-gall teratomas showing development 



of shoots from leaves 444 



341. Crown-gall tumors and malformation on inoculated tobacco produced 



with the carnation isolation of Bacterium tumefaciens (fig. 337) 447 



342. Delayed crown-gall teratoma on inoculated orange stem 448 



343. Inoculated, slow-growing, hard, crown-gall teratoma on mango 450 



344. A. An embryomatous portion of the mango tumor (fig. 343) enlarged. 



B. Crown gall in center of an inoculated young orange fruit 452 



