Success, how attained, 659 

 Sugar beet, 



crown gall on, 414, 420, 422 



leaf spot, 474 



Metcalf 's soft rot, 474 



tubercle of, 50, 472, 474 

 Sugar cane, 



bacterial disease of, in South 

 America, 54 



Cobb's disease of, 52, 473 



period of incubation in, 17 



Fiji disease, 476 



Sereh, 52, 476 



stripe disease (mosaic), 476 

 Sugar in tumors, 563 

 Summaries, importance of, 648 

 Supernumerary organs, 50 

 Susceptibility, period of greatest, 8 

 Swedes, rot of, 66 



Sweet brier, frondose gall on, 552, 554 

 Sweet corn, Stewart's disease of, 160. 



(See Stewart's disease.) 

 Symbiosis, 41 

 Syringes, 111 



Team work, necessary in research, 656 

 Temperature, arrangements for con- 

 trolling, for culture work, 81 

 Teratosis, production of in Begonia, 



574-630 

 Teratoma, on potato, 508, 540 

 Text-books recommended for study, 76 

 Thermo-regulators, Roux, 81, 109 

 Thermostats, 109 



Rohrbeck, 81 

 Tyloses in plants, 357, 477 



figures illustrating, 200, 478, 479, 

 480 

 Titration, apparatus for, 80 

 Titration of media, how practiced in 



my laboratory, 132 

 Tobacco, 



bacterial disease of, in South Africa, 

 54 



brown rot of, 177. (See also Bac- 

 terium solanacearum.) 



disease of, in Sumatra and Java, 

 economic importance of, 52 



leaf-spots of, 54, 476 



wilt, in China, 53 



Tobacco wilt, in Cuba and Porto Rico, 

 182 

 in Japan, 53 



in Southern United States, 55 

 Tomato, 



bacterial canker of, 202. (See also 

 Aplanobacter michiganense.) 

 appearance of the disease, 202 

 cause of the disease, 205 

 figures illustrating, 203, 204, 205, 



206, 210, 211, 212 

 geographical distribution, 205 

 histology, figures illustrating, 



207, 208, 209, 213, 214, 215 

 infectious nature of, 202, 216 

 isolation of causal organism, 207 

 literature, 222 



parasitic organism probably 



seed-borne, 202 

 resemblance to a disease of pota- 

 toes in Germany, 207 

 resemblance to brown rot, 202 

 restricted growth of pathogen in 



certain media, 206, 207, 217 

 signs of the disease, 202 

 staining of tissues, 202 

 stomatal infection common, 202 

 technical description of patho- 

 gen, 205 

 tissues attacked, 202 

 transmission of disease, 202 

 type of disease, 202 

 brown rot of, 177. (See Bacterium 



solanacearum.) 

 oedema of, 489, 508, 509 

 wilt, found in South Africa, 54 

 Topics suitable for special study, 474, 



475, 476, 477 

 Toxins, production of, by bacteria, 46 

 Transfer chambers for making cultures, 



80 

 Transmission of disease, agents, 19-34 

 by aphides, 159, 384 

 by bees, 25, 30, 360, 384 

 by beetles, 30, 134, 135, 199 

 by bugs, 384 

 by birds, 25, 384 

 by bulbs, 20 



by diseased refuse, 159, 278 

 by dung-heap, 21 



