74 Infection 



portance. It is called after its discoverer the Oppler-Boas bacillus,* 

 also on account of angulations found in its threads, Bacillus gen- 

 iculatus. It is a large bacillus, tending to form long threads easily 

 seen without an oil-immersion lens. It is probably non-motile, does 

 not form spores, stains by Gram's method, and is said by Emoryf 

 to divide longitudinally as well as transversely. This, as he says, will,' 

 if proved to be correct, be a most important means of identifying the 

 species. Cultures are easily made in media acidified with lactic acid. 



The intestine receives such micro-organisms as have survived 

 whatever destructive influences the gastric juices may have exerted, 

 and its alkaUne contents, rich in proteins and carbohydrates in 

 solution, are eminently appropriate for bacterial life. The flora of 

 the intestine is, therefore, increased in number and variety of 

 organisms as we descend from its beginning to its end. In the small 

 intestine there may be no bacteria in the upper part of the jejunum, 

 but in most cases Bacillus lactis aerogenes and bacilli of the colon 

 groups are found. These increase in number as the iUocecal valve 

 is reached. The cecum shows large numbers 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 the organisms of the bowel 

 and their distribution has been made by Kohlbrugge.J Kendall§ 

 finds the meconium contained in the intestine of the new-born to be 

 sterile, the first bacteria making their appearance in the course of 

 eighteen or twenty-four hours. The initial flora is not characteristic. 

 The most interesting early organism in the meconium is a large ba- 

 cillus with a terminal spore, and resembhng the Bacillus tetani. It is 

 supposed to be Bacillus putrificus of Bienstock. "Other spore- 

 bearing bacteria both aerobic and anaerobic are usually present 

 in the meconium at this period. Of these Bacillus aerogenes 

 capsulatus and members of the Bacillus mesentericus group are the 

 best known. Bacillus coli, Bacillus proteus. Bacillus lactis aerogenes 

 and Micrococcus ovalis also commonfy occur." 



As the infant nourished at the breast becomes accustomed to the 

 new condition, and settles down to its milk diet the bacteria through- 

 out the alimentary canal become more numerous, the spore-bearing 

 types disappear rather abruptly, and the coccal forms and Gram- 

 negative bacilU of the B . coU and B . aerogenes types diminish relatively, 

 though they never entirely disappear. At the same time a long 

 slender bacillus occurring singly and in pairs, or in groups with their 

 axes parallel becomes strikingly prominent. They are slightly 



He (( 



Deutsche med. Wochenschrift," 1905, No. S- 

 t "Bacteriology and Hematology," p. 114. 

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

 § "Bacteriology, General, Pathological and Intestinal," Phila., 1916. 



