INFECTIONS OF THE DIGESTIVE TRACT 57 



with the onset of the milk-stool period. B. lactis aero- 

 genes was not found in the meconial stools. It appears 

 from Moro's observations, which I can corroborate, that 

 bacteria of the B. coli type may appear in agar plates 

 as early as ten hours after birth. Somewhat later, 

 various coccal forms may appear ; in the course of forty- 

 eight hours the bacterioscopic fields may show bacilli 

 which are Gram-positive and which in some instances 

 show typical bifurcations and through anaerobic culture 

 on sugar-agar may prove to be B. bifidus communis. 

 Still a little later, B. aerogenes capsulatus may make its 

 appearance, and about this time, too, spore-bearing cylin- 

 drical bacilli may appear. The very early occurrence 

 of B. bifidus in the meconium is a striking fact, since it 

 appears hardly possible to explain its presence there 

 so soon after birth on the supposition that bifidus has 

 entered by the portal of the mouth. It appears, there- 

 fore, upon the whole, extremely probable that the infec- 

 tion of the gut in newly born children with B. bifidus 

 communis is by way of the anus and that the air is the 

 source of the infection. It is interesting to note that 

 even before the appearance of B. bifidus in the meconial 

 stools the colon bacillus is represented there. The pres- 

 ence of the colon bacillus, like the presence of B. bifidus, 

 cannot be explained at this early period by an invasion 

 through the mouth, although, as already stated, the colon 

 bacillus may enter the intestine by way of the mouth at 

 a later period. Both these organisms, B. bifidus and B. 

 coli, possess motility, and it is probably by virtue of this 

 motility that they find their way into the lower intestinal 



