CHAPTER XXXV. 



CLASSIFICATION AND DESCRIPTION OF 8PK2EB. 



Ix reviewing the history of the various classifications which h.-.vt- 

 from time to time been proposed, we shall see that the gradual 

 improvements in the means of studying such minute* <>!! 

 the methods of cultivating them artificially, and of studying th<-ii 

 chemistry and physiology, and the ever-increasing revelations of the 

 microscope, have resulted in establishing these microscopic object 

 members of the vegetable kingdom, ranking among the lowest form* 

 of fungi, but with regard to the division into genera and species we 

 are still in a position of doubt and uncertainly. 



Miiller, in 1773, was the first to suggest a classification. I It- 

 established two genera, Monas and Vibrio, and groups! them with 

 the Infusoria. In 1824 Bory de Saint Vincent al>o attcmptr.l 

 a classification; but it was not until Ehrenberg in 1838, ami 

 Dujardin in 1841, worked at the subject, that .1 M-i -ntific distinction 

 of species was attempted. 



Ehrenberg described four genera : 



I. Bacterium . . filaments straight, rigid. 



II. Vibrio . filaments snake-like, flex ihlt 



III. Spirillum . . filaments spiral, rigid. 



IV. Spirochseta . . filaments spiral, flexible. 



Dujardin united Spirillum and Spirocli 1 classed 



thus : 



I. Bacterium . . filaments rigid, vacillating. 



II. Vibrio . filaments flexible, undolatory. 



III. Spirillum . . filaments spiral, rotatory. 



Bacteria were still considered as Ini'ii>ori:.. l.nt in !*"-' Perty 

 maintained that some of the small->t living organism befcoge 

 the animal and others to the vegetable kingdom, an- 1 that Vil.no 

 without question belonged to the latter. In 1853 Robin point, ,i 



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