340 THE MICROSCOPIST. 



tion, and the significance of the low organisms, new facts 

 in regard to the extension of national diseases, and also a 

 number of quite positive discoveries by numerous investi- 

 gators, have removed the old opposition to the theory, or 

 even been the means of furnishing definite proof of its 

 correctness." This quotation expresses the most san- 

 guine views of the adherents of this theory. 



We have already referred to the connection of mould 

 and yeast fungi with the process of fermentation, and it 

 is quite possible that the introduction of such germs into 

 the body may produce slight irritations and even inflam- 

 mations from the increase and multiplication of the fungi, 

 and the chemical changes induced by them. We have 

 also seen that fungi are causes of putrefaction as well as 

 of fermentation in organic bodies. Yet the diseases of 

 the human body, in which fungi have been proved to be 

 real causes, are but few. Among vegetable diseases 

 caused by fungi are the rust, smut, etc., of our grains, the 

 " vine disease," " potato disease," etc. Among animal 

 diseases of this kind are some affections of caterpillars, 

 flies, etc., and gangrene of the spleen in mammals. In 

 splenic gangrene, however, as well as in mycosis intesti- 

 nalis, pyaemia, diphtheria, etc., in which fungi occur, the 

 bacteria may be merely the carriers of the disease, or may 

 develop because of special pabulum furnished by the dis- 

 eased structure which is not present in the normal state. 



Another theory of disease germs has been published by 

 Dr. Eeale, which regards them as minute masses of de- 

 praved bioplasm, originated probably in man's own body, 

 or in the bodies of some of the animals domesticated by 

 man. 



Both theories may be true in reference to the cases to 

 which they are applicable. They do not even necessarily 

 exclude each other. Each kind of disease-germ, bioplastic 

 or fungoid, may have a range of action peculiarly its own. 



Dr. Beale's views seem to apply to a much wider field 



