THE BEGINNINGS OF LIFE. 345 



hours a multitude of isolated and motionless specks 

 make their appearance and speedily develop, within the 

 substance of the cell, into well-formed Bacteria. This 

 takes place when no notable amount of Bacteria exists 

 in the surrounding fluid , and, indeed, from the mode of 

 appearance, distribution, and development of the parti- 

 cles within the cell, it is obvious that, on the c germ- 

 theory, 3 we should have to believe that each epithelial 

 cell which goes through this transformation is saturated 

 with as many invisible germs of Bacteria as would cor- 

 respond to the motionless and scattered organisms 

 which are subsequently imbedded in its substance. In 

 their earliest stage these units do not multiply; and 

 before the contents of the cell become fluid, the relative 

 positions of the individualizing units are maintained 

 and may be well observed. 



Thus, then, we have the possibility of independent 

 organisms arising within unhealthy or dying cells, either 

 by means of a heterogenetic modification of some al- 

 ready existing particles or globules, or by a process of 

 new birth in the fluid or semi-fluid matter of the cell. 

 By one or other of these modes, we believe that the 

 various Fungi and other allied organisms, which are so 

 frequently met with in the bodies of animals as well as 

 of plants, are capable of arising de novo. 



In the moister mucous membranes, Bacteria ) Vikriones^ 

 and Leptothrix are most abundant; and, more rarely, 

 larger Fungus-germs occur, which soon develop an 



