SPIRILLA RESEMBLING CHOLERA SPIRILLUM. 397 



reacts negatively to Pfeiffer's test ; in most respects it closely resembles 

 the cholera organism. Another spirillum (v. Ivanoff} was cultivated 

 by Ivanoff from the stools of a typhoid patient after these had been 

 diluted with water. This organism differed somewhat in the appear- 

 ance of its colonies and in its great tendency to grow out in the form 

 of long threads, but Pfeiffer found that it reacted to his test in the 

 same way as the cholera organism, and he considered that it was really 

 a variety of the cholera organism. No spirilla could be found micro- 

 scopically in the stools in this case, and Pfeiffer is of the opinion that 

 the organism gained entrance accidentally. These examples will show 

 how differences of opinion, even amongst authorities, might arise as to 

 whether a certain spirillum were really the cholera organism or a 

 distinct species resembling it in some respects. 



A few examples may also be given of organisms cul- 

 tivated from cases in which cholera- like symptoms were 

 present. 



The vibrio of Massowah was cultivated by Pasquale from a case 

 during a small epidemic of cholera. This organism so closely re- 

 sembles Koch's spirillum that it was accepted by several authorities as 

 the true cholera organism, and, as already stated, Metchnikoff pro- 

 duced by it cholera symptoms in the human subject, and also the 

 cholera-like disease in young rabbits. It possesses four flagella, has a 

 high degree of virulence, producing septicaemia both in guinea-pigs 

 and pigeons, and its colonies in plates differ somewhat from the 

 cholera organism. Moreover, it reacts negatively to Pfeiffer's test. 

 Another organism, the v. Gindha, was cultivated by Pasquale from a 

 well, and was at first accepted by Pfeiffer as the cholera organism, but 

 afterwards rejected, chiefly because it failed to give the specific im- 

 munity reaction. It also differs somewhat from the cholera organism 

 in its pathogenic effects, and it fails to give the cholera-red reaction 

 or gives it very faintly. 



Pestana and Bettencourt also cultivated a species of spirillum from a 

 number of cases during an epidemic in Lisbon an epidemic in which 

 there were symptoms of gastro-enteritis, although only in a few instances 

 did the disease resemble cholera. They also cultivated the same 

 organism from the drinking water. It differs from the cholera organism 

 in the appearance of its colonies and of puncture cultures in gelatine. 

 It has very feeble pathogenic effects, and gives a very faint, or no, 

 cholera-red reaction. To Pfeiffer's test it also reacts negatively. 

 Another spirillum (v. Romanus) was obtained by Celli and Santori 

 from twelve out of forty-four cases where there were the symptoms of 

 mild cholera. This organism does not give the cholera-red reaction, 

 nor is it pathogenic for animals. They look upon it as a " transitory 

 variety " of the cholera organism, though sufficient evidence for this 

 view is not adduced. 



