56 INFECTIONS OF THE DIGESTIVE TRACT 



The first milk stool appeared on the fifth day and con- 

 tained the physiological flora. It is evident, therefore, 

 that the organisms present in this case must have had 

 another source. The possibility of the presence of 

 B. bifidus in the mouth of the child was then excluded by 

 the observation that anaerobic organisms do not grow 

 from the mouth secretion of newly bora children. As 

 it thus appeared clear that the infection of the intestinal 

 tract by bifidus does not occur by way of the mouth, 

 there remained only one possibility ; namely, that the 

 infection occurred through the anus. A study of the 

 organisms of the meconium has made it appear very 

 probable that this is the mode of infection with B. 

 bifidus. 



The bacteria of the meconium were first carefully stud- 

 ied by Escherich, who pointed out that the originally 

 sterile meconium very easily acquires bacteria charac- 

 terized by their relative sparcity and considerable variety 

 and the presence of certain spore-bearing organisms. 



Among the constant flora are coccal forms in relatively 

 large numbers; some short bacilli, including B. coli 

 communis, and some varieties of spore-bearers. One 

 form of spore-bearer is the so-called headlet bacterium 

 already mentioned, and a thicker form which was iden- 

 tified by Kohn as B. subtilis. On gelatin plates the most 

 abundant organisms are usually B. coli communis, which 

 is sometimes associated with liquefying streptococci. In 

 fact, the presence of liquefying bacteria in the meconium 

 is rather characteristic of the meconial period, and this 

 peculiarity, under normal conditions, ceases abruptly 



