BACTERIA AS PLANTS. 11 



some attention to these little organisms. Among 

 them we should perhaps mention Von Gleichen, 

 Muller, Spallanzani, and Needham. Each of 

 these, as well as others, made some contributions 

 to our knowledge of microscopical life, and among 

 other organisms studied those which we now call 

 bacteria. Speculations were even made at these 

 early dates of the possible causal connection of 

 these organisms with diseases, and for a little the 

 medical profession was interested in the sugges- 

 tion. It was impossible then, however, to obtain 

 any evidence for the truth of this speculation, and 

 it was abandoned as unfounded, and even forgot- 

 ten completely, until revived again about the mid- 

 dle of the ipth century. During this century 

 of wonder a sufficiency of exactness was, how- 

 ever, introduced into the study of microscopic or- 

 ganisms to call for the use of names, and we find 

 Muller using the names of Monas, Proteus, Vibrio, 

 Bacillus, and Spirillum, names which still continue 

 in use, although commonly with a different signifi- 

 cance from that given them by Muller. Muller 

 did indeed make a study sufficient to recognise 

 the several distinct types, and attempted to clas- 

 sify these bodies. They were not regarded as of 

 much importance, but simply as the most minute 

 organisms known. 



Nothing of importance came from this work, 

 however, partly because of the inadequacy of the 

 microscopes of the day, and partly because of a 

 failure to understand the real problems at issue. 

 When we remember the minuteness of the bacteria, 

 the impossibility of studying any one of them for 

 more than a few moments at a time only so long, 

 in fact, as it can be followed under a microscope; 

 when we remember, too, the imperfection of the 



