THE CUCURBIT WILT: TRANSMISSION 145 



Can you obtain the disease by soil infection (a) through 

 wounded roots; (5) through unwounded roots? Contrast with 

 No. IV. 



LITERATURE 



For Hterature, etc., consult: Wilt of Cucurbits in ''Bacteria 

 in Relation to Plant Diseases," Vol. II, pp. 209-299, Carnegie 

 Institution of Washington, 1911, and Ibid., Vol. I (1905) Plates 

 3 and 23, and Figs. 8, 9, 13, 14, 21, 47, 48, 68, 69. Also papers 

 by Rand, Rand and Enlows and Rand and Cash. 



The first paper on the subject was read by the writer in 

 August, 1893, at a meeting of the American Association for 

 the advancement of Science {Bot. Gaz., Sept., 1893). This was 

 my first contribution to the literature of bacterial diseases of 

 plants. The name Bacillus tracheiphilus was first published in 

 1895 in Centralb.f. Bakt. u. Par.. II Abt., I Bd., 1895, p. 364. 



11. THE BLACK ROT OF CRUCIFERS 



Type. — This is a common vascular disease of cabbage, cauli- 

 flower, kohlrabi, kale, rape, turnips, and mustard. Often whole 

 fields are destroyed (Fig. 79). Dr. F. C. von Faber also found 



Fig. 79. — Cabbage field in Wisconsin, showing all of the plants attacked and 

 destroyed by Bacterium carnpestre. Not a head was harvested. {After Russell.) 



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