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Black Rot of Cabbage. 

 Baccillus campestre (Pam.) Sm. on Brassica oleracea and B. campestris. 

 Infection takes place through the water pores of the leaves. The mar- 

 gins become affected and later the whole leaf withers and dies from throm- 

 bosis, i. e. by the plugging up of the xylem vessels by the bacilli. It has 

 been shown while the bacilli will die when exposed from 8-10 days on a 

 dry cover glass, they are able to live ten to thirteen months on the smooth 

 surface of a cabbage seed, and that they often pass the winter in such a 

 position. 1 



Stewart's Sweet Corn Disease. 

 Bacterium stewartii. Sm. on Zea Mais. 

 This is a thrombotic disease of sweet corn that is believed to be dis- 

 seminated from year to year chiefly by means of bacteria clinging to the 

 seed. 2 



1 < Stewart PC l Vitality of the Cabbage Black Rot Germ on Cabbage Seed. N. Y. 

 ' lPrucha,'M.' J.' j Ex P- Sta - Bul - 251 - 1904 - 

 2. Stewart, F. C, A Bacterial Disease of Sweet Corn. N. Y. Exp. Sta. Bul. 139, 1897. 



