82 BEALE's PROTOPLASMIC THEORY. 



are always formed partly from the constituents of the 

 sugar ; viz., succinc and lactic acids, glycerine, propylic, 

 amylic, butylic, and caproylic alcohols, and probably 

 other substances still unknown (Watts' Diet.). Now, 

 if the process is catalytic, why is the whole sugar not 

 resolved into carbonic acid and alcohol ? In the true 

 catalytic formation of chlorine from hydrochloric acid by 

 oxygen and copper salts, the whole chlorine is evolved. 

 Besides all this there must always be furnished some 

 albuminous matter, in addition to the sugar, as pabu- 

 lum, and there is also produced cellulose and new pro- 

 toplasm. Instead, therefore, of a more or less complex, 

 merely chemical, change the yeast fermentation should 

 be represented thus. A portion of yeast protoplasm 

 converts into additional living matter like itself, some 

 sugar with a trace of albuminous matter and salts. At 

 the same time the surface layer dies and is converted 

 into cellulose which remains as the cell wall, and the 

 above products which are dissolved or volatilized away. 

 Likewise in the growth of bacteria we observe the 

 same formation of by-products, whatever be the nature 

 of the albuminous matters by whose destruction these 

 creatures live. But what is more remarkable, Cohn 

 found, and his observations have been confirmed by 

 those of Mr. Dallinger and myself, that a specific odour 

 of putrefaction is given out when they (bacteria and 

 infusoria up to the rank of paramecia) are nourished 

 without any albumen, i.e., in a solution of tartrate of 

 ammonia with mineral salts. This shows that in growth, 

 the bacteria must form protoplasm out of the ammoni- 

 acal and other salts, and portions of it are then decom- 

 posed in vital acts. 



