OR I G IX OF LOWEST ORGANISMS, 



equilibrium, which has, perhaps, been necessitated 

 by molecular changes that have occurred during a 

 preceding period of growth. The living matter which 

 is no longer able to exist round a single centre, 

 re-arranges itself around two centres, as a result of 

 which, fission occurs. It seems only natural, there- 

 fore, that whilst this active work of molecular re- 

 arrangement is going on, those other molecular 

 movements which occasion the actual locomotion 

 of the organism from place to place, should be more 

 or less interfered with. 



This is the one and only mode of multiplication of 

 Bacteria and of Torulce which is actually known to 

 occur ; and such a limitation is in accordance with the 

 more general fact, that processes of fission or gemma- 

 tion are the only means of reproduction that are known 

 to occur in the lower kinds of organisms, belonging to 

 the PROTISTIC kingdom. 



However well this process of fission may have 

 been established, as a frequent mode of reproduction 

 of Bacteria, such a fact does not lend any support to 

 the notion that these are necessarily distinct and 

 independent organisms. Torulce (of which beer-yeast 

 is the most familiar example) may similarly undergo 

 this process of mere vegetative repetition to an 

 indefinite extent, whilst only some of the products 

 develop into fungi. The gonidia of lichens may also 

 reproduce indefinitely in this fashion, and only some 

 of the products of multiplication may go on to the 



