TEXT-BOOK OP BACTERIOLOGY. 277 



incessant intermingling of these small objects can be seen. The 

 edge is bordered with quite short, delicate filaments. 



The appearance of the colonies differs wholly from that of the 

 comma bacilli, and a Finkler plate does not resemble at all a cholera 

 plate. Their difference becomes still greater in test-tube culture. 



In a four-day-old cholera puncture a thin thread clear as glass 

 will be seen, the air-vesicle above and the neatly -formed heaps of 

 bacteria below. In a culture of Finkler's bacterium of the same 

 age the gelatin is widely liquefied along the entire puncture, nearly 

 half of the gelatin being already changed into a turbid gray solution. 

 The form of the liquefied district in the solid gelatin produced by 

 the growth of the bacteria looks like a " trouser-leg " or a " stock- 

 ing," and the entire contents of the glass become liquefied after 

 about a week. A film of a smeary-white appearance is then formed 

 on the surface. 



Finkler-Prior's micro-organism spreads rapidly on agar as a 

 damp, slimy film, coating the whole surface in a short time. 



The cholera bacteria thrive on potatoes only at breeding 

 temperature, and produce a very characteristic yellowish-brown 

 growth; Finkler's vibrio grows on the slices at ordinary tempera- 

 ture and rapidly produces a grayish-yellow, slimy, shining layer 

 extending to the edge of the potato. It can live in milk, but soon 

 perishes in water. 



Koch has shown and Finkler confirmed that the latter's bacteria 

 can, under some circumstances, also display a pathogenic effect. If 

 they are brought (in the manner mentioned in connection with 

 the experimental infection with comma bacilli) into the stomach 

 of Guinea-pigs, part of them will die. But Finkler's vibrios are 

 not as poisonous as the genuine comma bacilli, their proportion 

 being 35 : 30 and 15 : 5 respectively. The post-mortem appearance, 

 too, is different, the intestine looking pale gray and its watery con- 

 tents developing a penetrating odor of putrefaction not met with in 

 the contents of the-cholera intestine. 



The differences thus briefly mentioned between the two kinds of 

 bacteria are, in fact, so considerable that they cannot be confounded. 

 The opinion originally held by Finkler and Prior regarding the 

 identity of their micro-organism with the genuine comma bacillus 

 can be explained only by the inefficiency of their mode of examina- 

 tion. They afterward became convinced of their error; but they 

 did not want to drop their protege altogether, and wished, after the 

 loss of its first claims, to uphold it at least a's the origin of cholera 

 morbus. 



It is true that the vibrio was first observed in the dejections of 



