Etiologic investigation has made further progress through the results of collective bacteriologic work in America, which have been reported by Flexner and Holt, and confirmed by the researches of other authors (Leiner, Jehle). From these results it appears that in the majority of cases of .summer diarrhata it is possible to obtain from certain parts of freshly- passed stools by certain special methods of cultivation, various types of dysentery bacilli, which are also found to some extent in the normal stools of healthy infants. There is con siderable ground for believing that further studies in this direction will lead to a substantial change in our pathogenetic point of view.
This should also result from a refinement of our eulture methods, particularly perfecting of the technique of growing; anaerobes', which will probably give unexpected results (Passini).
The bacterium coli, which formerly occupied the foreground, and was considered the exciting cause of all possible pathologic processes, (a view which, as I pointed out a number of years ago, was not suffi ciently proved) has now retreated somewhat into the background, because the total armament or modern bacterial diagnosis, such as serum reaction, formation of flagell, and SO forth, has not been conducive to increasing its reputation (Escherich. Pfaundler, Nobecourt. et al.).
A great and lasting service was undoubtedly performed by Czerny, Keller, and the other active co-workers of the Breslau children's clinic, when they forsook the one sided bacteriologic standpoint in their studies, and elucidated the important bearing of disturbances in the processes of metabolism upon the pathology of diseases of nutrition. I shall refer to the detailed researches of these authors in another part of this work. if they also proceeded at first in a somewhat one-sided direc tion, and gave to an ambiguous and inconstant finding too marked a significance, they nevertheless furnished us with valuable insight into the mechanism of assimilative processes, and established a better understanding of the origin, and a rational standpoint for the thera peutics of the diseases of nutrition. We shall speak more thoroughly of all this in the appropriate chapter.