304 ROMANCE OF LOW LIFE AMONGST PLANTS. 



yeast-plant, or torula, is formed in the more rapid 

 fermentation, taking place at more elevated tempera- 

 tures.' ^ The vinegar-plant, commonly so called, is a 

 tough, leathery mass, often used by private families 

 to make vinegar out of a solution of sugar and 

 treacle ; but the same plant exists in a more delicate 

 and diffused form when other modes of vineear- 

 making are employed ; and M. Pasteur shows that 

 it coats the shavings or twigs over which some manu- 

 facturers cause a suitable liquid to flow when they 

 desire to promote its acetification. If a thin piece of 

 the large tough vinegar-plant is examined microscopi- 

 cally, a moderate power suffices to show what the 

 ' Micrographic Dictionary' describes, namely, an 

 unorganized jelly and cellular structures of many 

 shapes, often resembling coherent cells of yeast, 

 others being like oidium, etc. It is also, in those I 

 have examined, easy to see something like an en- 

 tangled mass of minute threads ; but, when this 

 structure is carefully treated, myriads of bacterium 

 bodies appear, and are found to constitute the chief 

 bulk of the plant itself I am not aware that these 

 bacterium bodies have been described before, and I 

 will therefore explain the process by which I became 

 acquainted with their existence. First, a small thin 

 strip of the vinegar-plant should be torn off from any 

 part on or below the surface. This should be placed 

 upon a glass slide, moistened with a drop of water, 

 and stretched out by means of a camel-hair pencil- 

 holder, and the back of a penknife. When reduced 



> "This theory is doubtful, as the alcoholic fermentation goes on 

 slowly and at low temperatures with the German sediment yeast," 



