en via] BACTERIUM. ci 



fluids, indeed they form the essential cause or ferment of 

 decomposition, being the true saprogenous ferment (Cohn). 

 They are invested in a thick membrane, and are flagellate. 

 With the end of putrefaction they disappear. They grow well 

 in Cohn's nourishing fluid, and I have found them as constant 

 inhabitants of unfiltered distilled water in the laboratory ; so 

 much so that with a drop of this water I am always able to 

 start a copious growth of bacterium termo in pork broth, Agar- 

 Agar, &c. When cultivated in the incubator at 32 to 36 C. in 



/ r- / 



FIG. 29 BACTERIUM TERMO FROM Fio. 30. ZOOOT.CEA OF BACTERIUM 



AS ARTIFICIAL CULTURE. TEKMO. 



suitable nourishing material (pork broth, chicken broth,) they 

 produce a uniform turbidity, and after several days an attempt 

 at a pellicle, the whole nourishing fluid becoming thicker. 

 But after from several days to a few weeks the cultures die, 

 a fact which distinguishes them from all other bacteria. Grow- 

 ing in solid Agar-Agar, and peptone mixture, they produce an 

 imperfect liquefaction, numerous gas bubbles appearing in the 

 material. 



' o **. 

 ' f 



FIG. 31. BACTERIUM LINTOT.A. 



(7>) Bacterium lineola (Vibrio lineola, Ehrenberg, Dujardin), 

 differs from bacterium termo in being longer and thicker. 

 The cells are about 003 to 0'005 mm. long, about O'OOIS mm. 

 thick. They occur in well-water and stagnant water, where 

 no distinct putrefaction is going on, and form zooglcea, and 

 pellicles, on the surface of potatoes and various infusions. 



2. Zymogenic bacteria. Two kinds are known : Bacterium 

 lactis and bacterium aceti. 



(a) Bacterium lactis. According to Pasteur, these bacteria 



