440 A MANUAL OF BACTERIOLOGY 



to be noted that vibrios may also be present in the normal 

 intestinal tract of man and animals, and may therefore 

 gain access to streams (Sanarelli). D unbar similarly, from 

 the Elbe, Rhine, and other rivers, isolated a number of 

 vibrios which could not be distinguished from the cholera 

 vibrios (Spirillum Elwers). It was afterwards noticed that 

 some of these under certain conditions of oxidation and 

 temperature became phosphorescent, 1 but Rumpel 2 has 

 also found that cultures of the genuine cholera vibrio may 

 exhibit phosphorescence, so this cannot be used as a 

 differential character for the separation of non- choleraic 

 forms. Neisser isolated a vibrio, which he termed Vibrio 

 Berolinensis, which agreed with the cholera vibrio in every 

 particular except that the colonies in a gelatin plate in 

 forty-eight hours were invisible to the naked eye. Heider 

 found in the Danube a spirillum, named by him the Vibrio 

 Danubicus, which resembled the cholera vibrio closely, 

 but its colonies were somewhat different, and it was more 

 actively pathogenic to mice. Ivanoff similarly obtained a 

 vibrio which could only be distinguished from cholera by 

 the finer granulation of its colonies and more distinct 

 spiral form. Lastly, there is the Vibrio Massowah, isolated 

 from an epidemic of cholera at Massowah, which differs 

 from the Koch vibrio in having two terminal flagella at 

 each end. Cunningham has also described several vibrios 

 differing but slightly from the cholera vibrio. 



Applying the Pfeiffer and agglutination tests to the 

 vibrios in question, the following results were obtained. 

 In the first place, each of the organisms gives a complete 

 positive reaction to both tests with its own serum ; this, 

 of course, is only to be expected. Pfeiffer found that, 

 using his reaction, the variety Ivanoff gave a positive 

 reaction with cholera serum, and Durham found that 



1 Centr.f. Bakt. (l tc Abt.), xviii, 1895, p. 424 (Kutscher). 



2 Munch, med. Wochensch)., 1895, No. 3. 



