PATHOGENIC BACTERIA. 



109 



FIG. 56. 



it being then impossible to distinguish any separate colonies. 

 The microscopic appearances in no way resemble the cholera 

 colony. 



Stab Cultures. The gelatine is liquefied 

 from above downwards, like a stocking in 

 appearance, and in three days completely 

 liquid. 



Potato. At ordinary temperature a 

 thick gray layer covering the whole sur- 

 face. 



Water. It soon perishes in water. 



Staining. Ordinary aniline dyes. 



Patlicgenesis. Foic man it has no spe- 

 cific action. If it is injected into Guinea 

 pigs, prepared as described under the 

 cholera bacillus, they die, the intestines 

 having a foul odor, and the bacilli then 

 found in great numbers. 



Spirillum Tyrogenum. (Den eke.) 



Origin. In 1885 Deneke found in old 

 cheese a spirillum very similar in appear- 

 ance to the cholera spirillum. 



Form. The same as the cholera vibrio. 



Properties. Very motile, liquefy gela- 

 tine. 



Growth. They grow quicker than the 

 cholera, and slower than the Finklcr ; they are also facultative 

 aerobic. 



Colonies. They at first resemble cholera colonies ; they have, 

 however, a yellow-green iridescence, and are somewhat more 

 irregular ; also grow more rapidly. 



Slab Cultures. A thick line along the needle-track and the 

 yellow colonies forming at the bottom, on the surface a bubble 

 of air similar to the cholera. The gelatine is all liquid in two 

 weeks. 



Potato. At brood-heat a thin yellow membrane, but not 

 always constant. 



Staining, as cholera bacillus. 



Stab Culture. (Finklcr- 

 Prior.) 



