THE OCCURRENCE OF ORGANISMS OF SANITARY 

 SIGNIFICANCE ON GRAINS * 



Samuel C. Prescott, 



WITH Co-operation of 



Erastus G. Smith, William J. Mixter and Selskar M. Gunn. 



In the development of bacteriology as applied to the sanitary 

 investigations of water supply, food supply, and sewage disposal, 

 the colon bacillus (B. coli) and certain streptococci {Strept. pyogenes) 

 have been regarded as of extraordinary significance. This has 

 been especially true of B. coli, which has been studied unceasingly 

 and by a large number of investigators almost ever since its dis- 

 covery by Emmerich in 1885. Having been early shown to be a 

 constant inhabitant of the human intestine, and present there in 

 vast numbers, it is not surprising that it has been regarded as of 

 great sanitary significance, and hence one of the most important 

 of bacteria. 



The streptococci here to be considered have received less atten- 

 tion, as they were more recently discovered, but as they have been 

 proved to be present in sewage, sewage effluents, and polluted 

 waters, and in the soil which receives the wastes of animal life, 

 these too have been regarded as characteristic of pollution, and their 

 detection has served as a striking confirmation of the evidence 

 offered by the finding of B. coli, as an index of fecal contamination 

 in water. 



It is the object of this paper to present a record — incomplete, 

 it may be — of the repeated isolation of organisms simulating these 

 "intestinal forms" in habitats other than those named, and to show 

 that they are actually identical in character with B. coli and Strept. 

 pyogenes, are abundant, and of constant occurrence on the surface 

 of grains, and in products of milling. 



HISTORICAL ACCOUNT. 



The opinion that B. coli is characteristic of pollution from human 

 sources only was long since proved to be erroneous, as it was shown 

 by Dyar and Keith,' Smith, ^ Flint, ^ Belitzer,^ and Moore and 



♦Received for publication March 31, 1906. 



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