308 APPENDIX. 
G. 
APPENDIX TO CHAPTER V. (p. 172). 
USEFUL MICROBES. 
We have said that numerous bacteria exist in the diges- 
tive canal of a man in good health. Recent researches by 
Duclaux, Richet, and Bourquelot tend to show that these 
microbes are not only innoxious, but that they play an 
active part in gastric digestion, and especially in the 
transmutation of albumins into peptones. Since they are, 
in fact, living ferments, the transmutation is retarded, if 
these microbes are eliminated. It is therefore probable 
that they manufacture pepsin. 
Pasteur’s experiments also tend to show that microbes 
aid the germination of plants. If the microbes contained 
in vegetable mould are withdrawn from it, without taking 
away any other constituent, germination is retarded, and 
effected with difficulty. 
H. 
APPENDIX TO CHAPTER V. (p. 241.) 
PTOMAINES OF FISH. 
Salt and smoked fish often produce in those who eat 
them violent poisoning, which may even end in death. 
Aurep, of Kharkov, has recently studied these causes, 
and ascribes them to a ptomaine secreted by a microbe, 
or perhaps evolved from the fish itself during life, under 
the morbid influence of this microbe. 
