84 Infection 



iliocecal valve is reached. The cecum shows large num- 

 bers of colon bacilli. The rectum contains, in addition, 

 many putrefactive organisms, such as Bacillus putrificus, 

 Bacillus proteus vulgaris, members of the Bacillus subtilis 

 group, and acid-producing organisms, such as Bacillus 

 acidophilus. 



An interesting and thorough study of these organisms 

 of the bowel and their distribution has been made by Kohl- 



Fig. 17. Sarcina ventriculi (Migula). 



brugge.* The total number of permanent residents is not 

 known. During infancy the predominating organism seems 

 to be Bacillus lactis aerogenes; during adult life, Bacillus 

 coli. Streptococci, especially Streptococcus coli gracilis, 

 are also very common, if not invariable, inhabitants of the 

 intestine. The total bacteria that finally appear in the 

 feces, according to the studies of Strasburgerf and Steele,J 

 may reach the enormous figure of 38 per cent, of the total 

 bulk. 



MacNeal, Latzer, and Kerr, in an elaborate work upon the 

 " Fecal Bacteria of Healthy Men," found that they furnished 

 46.3 per cent, of the total fecal nitrogen. 



: "Centralbl. f. Bakt.," etc., Bd. xxx, 1901, pp. 10 and 70. 

 f "Zeitschrift fur klin. med.," 1902, xuv, 5 and 6; 1903, XLVIII, 

 5 and 6. 



J "Jour. Amer. Med. Assoc.," Aug. 24, 1907, p. 647. 



$ "Journal of Infectious Diseases," 1909, vi, pp. 132, 571. 



