SIGNIFICANCE OF COLON GROUP IN WATER 147 



from standing grains. Gordan (1904) could not find 

 B. coli in .1 and .01 mg. samples of clean bran, but 

 isolated it easily from that of poor quality. Winslow 

 and Walker (1907) have recently reported the examina- 

 tion of 178 samples of grain and 40 samples of grasses 

 for B. coli without success. On the other hand, Diiggeli 

 (1904) found B. coli among the bacteria occurring on 

 the leaves of growing plants, although it was not one of 

 the most abundant species. Barthel, too (Barthel, 1906), 

 found B. coli widely distributed on plants from both cul- 

 tivated and uncultivated regions. BettencourtandBorges 

 (1908*) examined 35 samples of vegetables and cereals 

 purchased in open market and found 12 lactose ferment- 

 ers, of which 6 proved to be B. coli. It should be noted, 

 however, that the method of isolation used was direct 

 plating on Endo-medium, which is of course less sensitive 

 than the enrichment processes used by other workers. 



Neumann (1910) has recently studied the distribution 

 of colon bacilli on and in various food substances such as 

 bread, milk, butter and fruit. From fresh fruits immedi- 

 ately after picking he nevei* isolated them, but they were 

 present in a certain proportion of all the foods which had 

 been exposed to human contamination and the author 

 concludes that wherever human hands have been, there 

 will B. coli be found. Konrich (19 10) in a similar series 

 of investigations obtained positive results from 46 out of 

 100 .1 to .5 gm. samples of cultivated plants while leaves 

 of trees and grasses and herbs on waste places gave about 

 6 per cent positive results. Hay showed colon bacilli in 

 91 per cent of the 135 samples examined and grains in 

 55 per cent of 300 samples. Dr. L. A. Rogers of the 

 U. S. Bureau of Animal Industry has recently obtained 



