CLASSIFICATION OF THE BACTERIA. 71 



cus described by Hallier in several infectious mal- 

 adies. 



2. The Microbacteria. 



3. The Desmobacteria, including Bacillus, Lepto- 

 thrix, Beggiatoa, and Crenothrix. 



4. The Spirobacteria, including the three genera, 

 Vibrio, Spirillum, and Spirochceta. 



5. Finally, we will give some account of the Mer- 

 ismopedia, Sarcina, Ascococcus, Streptococcus, Myco~ 

 nostoc, Cladothrix, and Streptothrix. 



1. SPHEROBACTERIA, Cohn. 



The spherical bacteria are characterized by their 

 rounded or oval form, their small size, often less 

 than 1 fji. They are ordinarily isolated, often in 

 pairs (diplococcus), sometimes in a chain of several 

 articles (streptococcus = torula of Cohn), the my- 

 cothrix of Hallier and Itzigsohn, or in the form of 

 zooglcea when they are young and actively multi- 

 plying, and that of mycoderma, when they are 

 gathered upon the surface of liquids. They have 

 no spontaneous movement, but a simple molecular 

 trepidation. 



Functions : " The spherical bacteria are fer- 

 ments, not producing putrefaction, but substitu- 

 tions of another kind" (Cohn). 



Obs. According to the facts observed by Koch, 

 Cohn, Pasteur, Toussaint, upon the development 

 of certain bacteria, it is very probable that some 

 at least of the spherobacteria are spores of Bacil- 

 lus or of other bacteria; at least, the micrococci 

 and these spores are identical in form and aspect. 



