OF MICROSCOPIC FUNGUS. 195 



external membrane. PI. L, fig. 20, PI. II, figs, i and 2. 

 By degrees this assumes an appearance resembling that of 

 the body from which it has proceeded ; it increases in size ; 

 the membrane around it becomes thicker; its point of 

 attachment to its progenitor becomes less and less, until at 

 last it is completely separated, arid becomes a free and 

 independent particle, exactly resembling that from which it 

 sprang, except that it is smaller, and capable of growing and 

 giving rise to new individuals like itself, by a repetition of 

 the process by which it was formed. PI. I, fig. ib. See also 

 PI. II, figs, i and 2, in which the growth and multiplication 

 of the yeast fungus is well represented from an actual 

 specimen which was well stained by carmine. The manner 

 in which the little organism grows and multiplies will be 

 understood if these drawings be carefully examined. 



The above is one way in which the particles of a simple 

 microscopic fungus may multiply, but there are others. In 

 one of these, too, an orifice forms in the membrane of the 

 particle, and a little of the soft transparent material escapes, 

 but it does not separate as in the first case ; it remains in 

 connexion with the mass, and grows out into a narrow 

 thread-like process. PI. I, fig. ig. fig. 4. The membrane 

 on the external surface becomes thickened, and the whole 

 increases in breadth. Within the membrane is found trans- 

 parent matter, from which a number of little spherical 

 bodies or very minute growing particles like those observed 

 within the spherical spore may be obtained. It may be 

 that as this process grows, a thinning occurs in its wall, at 

 one or more points. A portion of the contents coming 

 into more immediate contact with the pabulum increases in 

 amount, and thus gives rises to the production of another 



o 2 



