478 



CHOLERA 



may also be mentioned that an organism which is apparently the same 

 as the vibrio Metchnikovi was cultivated by Pfuhl from water, and named 

 v. Nordhafeu. 



Finkler and Prior's Spirillum. These observers, shortly after Koch's 

 discovery of the cholera organism, separated a spirillum, in a case of 

 cholera nostras, from the stools after they had been allowed to decompose 

 for several days. There is, however, no evidence that the spirillum has 



any causal relationship to this or any 

 other disease in the human subject. 

 Morphologically it closely resembles 

 Koch's spirillum, and cannot be 

 distinguished from it by its micro- 

 scopical characters, although, on the 

 whole, it tends to be rather thicker 

 in the centre and more pointed at 

 the ends (Fig. 142). In cultures, 

 however, it presents marked differ- 

 ences. In puncture cultures on 

 gelatin it grows much more quickly, 

 and liquefaction is generally visible 

 within twenty -four hours. The 

 liquefaction spreads rapidly, and 

 usually in forty-eight hours it has 

 produced a funnel-shaped tube with 

 turbid contents, denser below (Fig. 

 141, B). In plate cultures the 

 growth of the colonies is proportion- 

 ately rapid. Before they have pro- 

 duced liquefaction around them, they 

 appear, unlike those of the cholera 

 organism, as minute spheres with 

 smooth margins. When liquefac- 

 tion occurs, they appear as little 

 spheres with turbid contents, which 

 rapidly increase in size ; ultimately 

 general liquefaction occurs. On 

 potatoes this organism grows well 

 at the ordinary temperature, and in 

 two or three days has formed a 

 slimy layer of greyish-yellow colour, 

 which rapidly spreads over the 

 potato. On all the media the 

 growth has a distinctly foetid odour. 

 A growth in peptone solution fails 

 to give the cholera-red reaction at 

 the end of twenty-four hours, though 

 later a faint reaction may appear. 

 An organism cultivated by Miller ( " Miller's Spirillum ") from the cavity 

 of a decayed tooth in a human subject is almost certainly the same 

 organism as Finkler and Prior's spirillum. 



Deneke's Spirillum. This organism was obtained from old cheese, and 

 is also known as the spirillum tyrogenum. It closely resembles Koch's 

 spirillum in microscopic appearances, though it is rather thinner and 

 smaller. Its growth in gelatin is also somewhat similar, but liquefaction 



A B 



FIG. 141. Puncture cultures in 

 peptone-gelatin. 



A. Metchnikoff's spirillum. Five 



days' growth. 



B. Finkler and Prior's spirillum. 



Four days' growth. 

 Natural size. 



