192 INFECTIONS OF THE DIGESTIVE TRACT 



bacteria. This neglect may be ascribed to the technical 

 difficulties connected with the study of microorganisms 

 whose growth is checked by minute traces of oxygen, 

 and not to any belief that such microorganisms are 

 unimportant. 1 There is in fact growing evidence that 

 the strict anaerobes play an important part in some 

 pathological processes which have their seat in the digest- 

 ive tract, and one may hazard the prediction that careful 

 studies of them will give us wholly new light on some 

 obscure forms of disease. 



Bacillus Putrificus. The organism described by 

 Bienstock as B. putrificus is a spore-forming strict 

 anaerobe, capable of actively attacking and hydrolyzing 

 native proteids, and like many such anaerobes able to 

 give rise to characteristic products of putrefaction, 

 including butyric acid and hydrogen. It forms hydro- 

 gen sulphide and mercaptan but not indol. Consid- 

 erable difference of opinion exists as to whether B. putri- 

 ficus is or is not a regular inhabitant of the normal 

 human intestine. 2 This question is bound up with the 

 question of the identity of the bacterium. Bienstock, 

 it should be noted, has lately brought forward evidence 



1 Tarozzi ("Ueber ein Leicht in aerober Weisse ausfiihrbares 

 Kulturmittel von einigen bis jetzt fur strenge Anaeroben gehal- 

 tenen Keimen," Centralbl. f. Bakt., xxxviii, I Abt., Orig., p. 619, 

 1905) has lately described a method by which it is possible to 

 obtain aerobic growths of organisms which have hitherto been 

 regarded as strict anaerobes, including B. aerogenes capsulatus, 

 B. botulinus, etc. 



2 Passini holds that he can generally obtain it; Bienstock states 

 that he cannot find it in normal persons. 



B. putrificus is widespread and may readily become a contami- 

 nation as it is common in laboratory dust. 



