INFECTIONS OF THE DIGESTIVE TRACT 63 



prominent inhabitant is B. cloacce, which is a more active 

 gas former than B. coli. In fermentation tubes contain- 

 ing milk it may induce an active gas production and 

 disruption of the coagulum which suggest the action of 

 B. aerogenes capsulatus. Sarcinse are often found, both 

 in the small and large intestine, and white yeasts are 

 occasionally present. As was first pointed out by 

 Rodella, 1 there are several forms of bacteria present in 

 the large intestine which are capable of dissolving and 

 peptonizing casein. These forms, which are sometimes 

 facultative anaerobes, sometimes obligate anaerobes, are 

 usually distinctly more abundant in bottle-fed children 

 than in nurslings. Staphylococcus pyogenes albus is one 

 of the peptonizing forms bacteria often present and 

 possesses the ability to liquefy both casein and gelatin. 

 Probably in the case of bottle-fed children this organism 

 is less important as a liquefier than some of the faculta- 

 tive and strict anaerobic bacilli. 2 



1 " Ueber die Bedeutung der im Sauglingsstuhle vorkommenden 

 Mikroorganismen mit besonderer Beriicksichtigung der anaeroben 

 Bakterien," Zeitschr. f, Hyg., xli, p. 470, 1902. 



2 The facultative and strict anaerobes are much more abundant 

 in the large intestines of bottle-fed children than in the intestines 

 of nurslings. I attach especial importance to the presence of B. 

 aerogenes capsulatus which, as already mentioned, is present in 

 only small numbers in the case of breast-fed children. The number 

 of these organisms is not necessarily larger in the intestines of 

 children fed on cow's milk, but as a rule even in children con- 

 sidered quite normal, their number, though still small, is greater 

 than in the case of nurslings. As compared with the number pres- 

 ent in the faeces of adults these bacteria are few. Another an- 

 aerobic organism which is sometimes found is the motile butyric 

 acid bacillus of Schottenfroh and Grassberger. Furthermore, B. 

 putrificus can be found in some instances in the stools of bottle- 



