516 Spirillum* of Gamaleia 



Agar-agar. Upon agar-agar this spirillum forms a thin 

 yellowish layer which spreads quickly over most of the sur- 

 face. 



Bouillon. In bouillon the growth of the organism is 

 characterized by a diffuse turbidity. No gas-formation 

 occurs in sugar-containing media. 



Potatoes. The culture upon potato is luxuriant if 

 grown in the incubating oven. It appears as a distinct 

 yellowish, moist film, and when examined microscopically 

 is seen to contain beautiful long spirals. 



Metabolic Products. The organism produces no indol. 



Pathogenesis. The spirillum of Denecke is mentioned 

 only because of its morphologic resemblance to the cholera 

 spirillum. It is not associated with any human disease. 

 Experiments, however, have shown that when the spirilla 

 are introduced into guinea-pigs whose gastric contents are 

 alkalinized and whose peristalsis is paralyzed with opium, 

 about 20 per cent, of the animals die. 



THE SPIRILLUM OF GAMALEIA* (VIBRIO METSCHNIKOVI). 



Resembling the cholera spirillum in morphology and 

 vegetation, and possibly, as has been suggested, a de- 

 scendant of the same original stock, is a spirillum which 

 Gamaleia cultivated from the intestines of chickens affected 

 with a disease similar to chicken-cholera. 



Morphology. This spirillum is a trifle shorter and 

 thicker than the cholera spirillum. It is a little more 

 curved, and has similar rounded ends (Fig. 156). It forms 

 long spirals in appropriate media, and is actively motile. 

 Each spirillum is provided with a terminal flagellum. No 

 spores have been demonstrated. 



Staining. The organism stains easily, the ends more 

 deeply than the center. It is not stained by Gram's method. 



Cultivation. It grows well both at the temperature of 

 the room and at that of incubation. 



Colonies. The colonies upon gelatin plates have a 

 marked resemblance to those of the cholera spirillum, yet 

 there is a difference; and as Pfeiffer says, "it is compara- 

 tively easy to differentiate between a plate of pure cholera 

 spirillum and a plate of pure Spirillum metschnikovi, yet it 



* "Ann. de 1'Inst. Pasteur," 1888. 



