418 



CHOLERA 



of pure culture in pigeons is followed by septicaemia, which produces a 

 fatal result usually within twenty-four hours. Inoculation with the same 

 quantity of cholera culture produces practically no result ; even with 

 large quantities death is rarely produced. The vibrio Metchnikovi 

 produces somewhat similar effects in the guinea-pig to those in the 



pigeon, subcutaneous inoculation 

 being followed by extensive haemor- 

 rhagic redema and a rapidly fatal 

 septicaemia. Young fowls can be 

 infected by feeding with virulent 

 cultures. We have evidence from 

 the work of Gamaleia that the toxins 

 of this organism have somewhat the 

 same action as those of the cholera 

 organism. 



The organism is therefore one 

 which very closely resembles the 

 cholera organism, the results on in- 

 oculating the pigeon offering the most 

 ready means of distinction. It gives 

 a negative reaction to Pfeiffer's test 

 that is, the properties of an anti- 

 cholera serum are not exerted against 

 it. It 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. Nordhafen. 



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 dis- 

 tinguished 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. 141). In cultures, 

 however, it presents marked differences. 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. 140, B). In plate 

 cultures the growth of the colonies is proportionately rapid. Before 

 they have produced liquefaction around them, they appear, unlike those 

 of the cholera organism, as minute spheres with smooth margins. When 

 liquefaction 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 



A B 



FIG. 140. Puncture cultures in 



peptone-gelatin. 



A. Metchnikoffs spirillum. Five 



days' growth. 



B. Finkler and Prior's spirillum. 

 Four days' growth. Natural size. 



