62 INFECTIONS OF THE DIGESTIVE TRACT 



bottle-fed children. We find especially that this resem- 

 blance holds true with regard to the B. lactis aerogenes 

 group, the B. coli group, the B. acidophilus group, and 

 the group of organisms which we have come to know as 

 B. bifidus. As regards B. bifidus, however, we find that 

 there is a striking difference between the nursling and the 

 bottle-fed child. In nurslings the B. bifidus is the domi- 

 nant type throughout the greater part of the large intes- 

 tine; in the bottle-fed child the group of B. bifidus is 

 fairly well represented, as a rule, throughout the large 

 intestine and also in the lower part of the small intestine, 

 but it is by no means the dominant organism. The place 

 of preponderance is, in this case, occupied by organisms 

 of the B. coli type, and we thus find that the microscopi- 

 cal picture in the case of the bottle-fed child shows us a 

 field in which a majority of the microorganisms present 

 are Gram-negative instead of Gram-positive, as is the 

 case in nurslings. In addition to these leading types 

 of organisms in the case of bottle-fed children we have to 

 include certain positive and negative diplococci, some 

 of which are seen in chains while others appear as di- 

 plococci only. An organism described by Kruse, 1 and 

 known as the Streptococcus lacticus, is almost always 

 present and appears to be identical with the streptococ- 

 cus of Hirsh-Libbmann. It possesses the power of 

 coagulating milk. Among the less constant aerobic 

 bacteria are the white staphylococci. Sometimes a 



1 " Das Verhaltnis der Milchsaurebakterien zum Streptococcus 

 lanceolatus (Pneumoniecoccus, Enterococcus,u.s.w.)," Centralbl. f. 

 Bakt., 1st Abt., Orig., xxxiv, p. 737, 1903. 



