﻿624 Halsted : Exposure and fungous Diseases 



that the warmth of the spring sun upon the moist upper surface 

 furnishes the conditions that favor the growth of the sporids. 



An examination of the stems, some of which were badly rusted, 

 showed that the side towards the center of the group of stalks 

 were the most affected. 



This leads naturally to a study that was made of bacteriosis in 

 beans briefly mentioned with an engraving in Mycological Notes in 

 the June issue of the Bulletin. 



''The rows ran nearly north and south and upon the east side 

 of the plants there was but a small amount of the bacteriosis 

 {Bacillus phaseoli Sm.) to be seen, while upon the west side nearly 

 every pod of the green flageolet variety was more or less blotched, 

 many of them literally covered with the bacterial ulcers, which 

 were in many instances of an amber color, due to the multitude 

 of the germs of the bacillus that had collected in a layer upon the 

 surface." 



Fully nine tenths of all the blotches were upon the western 

 sides of the pods and about two fifths of all the pods of the variety 

 in question were badly affected. 



Strong winds upon the 17th and 20th of September bent the 

 plants to the southeast, from which they did not fully recover. 

 As a result, at the time the above observations were made, Octo- 

 ber 5th, the plants all leaned several degrees from the perpendicu- 

 lar and some of the pods were likewise tilted. In short, the foliage 

 of the plants hung chiefly upon the eastern side of the row and had 

 done so for between two and three weeks, and therefore one side of 



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each pod was more exposed than the other, and that exposure was, 

 speaking generally, in the direction of the four o'clock sun. 



It had been previously observed that the leaves of the plants 

 under consideration were badly blighted for weeks before the pods 

 became noticeably injured, and it is not unlikely that the germs 

 were carried from the diseased leaves to the pods by the dripping 

 dews, in which case the side that was slightly inclined upward on 

 account of the slanting posture of the plants would receive a more 

 generous supply of the germs than the more protected underside. 



It is possible that the bending of the plants so exposed the 

 pods that they became more or less injured by the sun and thus 

 provided more favorable conditions for the development of the 



