332 PATHOGENIC BACTERIA. 



film, and when examined microscopically is seen to con- 

 tain long beautiful spirals. 



The organism sometimes produces indol, but is irreg- 

 ular in its action in this respect. 



The spirillum of Denecke is mentioned only because 

 of its morphological relation to the cholera spirillum, 

 not because of any pathogenesis which it possesses. It 

 probably is not associated with any human disease. Ex- 

 periments, however, have shown that when the spirilla 

 are introduced into the intestines of guinea-pigs whose 

 gastric contents are alkalinized and whose peristalsis is 



v ' > v*- ^*- - , . ir .-. 



x%<-r*iUHi # 



r .\ >V ',*>y s 

 V-*v-%if^ / ^' - 



^ . % *T^^ rf *^ 



FIG. 89. Spirillum Metchnikoff, from an agar-agar culture ; x 1000 (Itzerott 

 and Niemann). 



paralyzed with opium, about 20 per cent, of the animals 

 die from intestinal disease. 



The Spirillum of Gamale'ia (Spirillum Metchnikoff). 

 -Very closely related to the cholera spirillum in its 

 morphology and vegetation and possibly, as has been 

 suggested, a descendant of the same original stock, is the 

 spirillum which Gamale'ia cultivated from the intestines 

 of chickens affected with a disease similar to chicken- 

 cholera. This spirillum is a curved organism, a trifle 

 shorter and thicker than the cholera spirillum, a little 

 more curved, and with similar rounded ends (Fig. 89). 



