i 4 VEGETABLE GERMS. 



OF VEGETABLE GERMS. 



Of the Yeast Fungus. If on a warm summer's day 

 or in a warm room a piece of germinating yeast about 

 the size of a pin's head be placed upon a glass slide, 

 covered with very thin glass and gently pressed, so as 

 to form a very thin layer, and then examined under a 

 microscope having a magnifying power of about 300 

 diameters or upwards, numerous little transparent, 

 colourless, oval bodies will be seen all over the field. 

 The bioplasm of these may be coloured by carmine 

 (Figs. 6, 7, 8, plate I.). They vary in size much more 

 than is generally represented in published drawings 

 of them, and many are joined together. If the stratum 

 of yeast be made very thin, as may easily be effected 

 by firm even pressure upon the thin glass, numerous 

 very minute bodies will be observed amongst the well 

 marked yeast corpuscles. The yeast consists of the 

 distinct oval bodies, the minute particles (detached 

 germs), and a fluid in which both are suspended. 



If now the apparently smooth oval bodies be sub- 

 jected to examination under a still higher power 

 (1,000 diameters, or upwards), many of them will be 

 found to exhibit little eminences, which project from 

 various parts of the surface. Sometimes only one 

 such eminence, and sometimes as many as a dozen, 

 may be counted in connection with one oval yeast 

 cell (Fig. 7, plate I.). These are undetached germs ; 



