ORIGIN OF LO WEST OR GA NISMS. \ 7 



And although, to many, this may seem an extremely 

 improbable supposition, it is, nevertheless, one which 

 it . would be very difficult to disprove. The im- 

 probability of the notion is increased, moreover, 

 when we find that Bacteria, and even Torulcz, will 

 develop just as freely within closed cells taken from 

 the very centre of a vegetable tuber, as they will in 

 the midst of the more solid epithelial cell from the 

 inside of the mouth. If it be urged that in this latter 

 situation, there is the greatest chance of the cells 

 being brought into contact with Bacteria, and that 

 it must be considered possible for imaginary minute 

 offcasts from these Bacteria to make their own way 

 into the substance of the epithelial cell, I am quite 

 willing to grant the desirability of taking such possi- 

 bilities into consideration. But, at the same time, 

 it seems all the less likely that the actual occurrence 

 of the Bacteria is explicable on these grounds, be- 

 cause we find them developing just as freely within 

 the cells freshly cut from the centre of a tuberous 

 root, or we may find them already developed within 

 these cells, if the root has begun to decay. To suppose 

 that actual germs of Bacteria and of Torulce are 

 uniformly distributed throughout the tissues of higher 

 organisms, is to harbour a hypothesis which would 

 appear to many to be devoid of all probability more 

 especially when the heterogenetic mode of origin of 

 larger and higher organisms is a matter of absolute 

 certainty. 



C 



