CH.VL] VALUE OF CHOLERAIC COMMA-BACILLI. 113 



justification for a general statement of this kind than if one 

 were to lay it down that two species notoriously different in 

 chemical and physiological respects must always show 

 different characters in the artificial cultivations commonly 

 employed; for the contrary has been proved as regards 

 several species. It has for instance been shown that the 

 capsulated oval coccus first discovered by Friedlander in 

 connection with croupous pneumonia is not the only species 

 that in morphological respects and in artificial cultures 

 possesses the characters he described. Of other bacteria, 

 e.g. streptococcus (some of those studied by Rosenbach, by 

 Uffendi and others), the same holds good. 



Comparing for instance the behaviour of some of the non- 

 pathogenic micrococci studied by these last two observers in 

 artificial cultures with that of some of the pathogenic micro- 

 cocci (e.g. of erysipelas and of vaccinia) the similarity is very 

 striking; nevertheless the physiological action is totally 

 different. The same is to be said of the bacillus of typhoid 

 fever, and of some of the species of the proteus of Hauser. If 

 two kinds of bacteria differ in mode of growth, cateris paribus, 

 in the same culture media, I think it will be admitted that 

 they are probably different species. While then it will be ad- 

 mitted that Koch's comma-bacilli must be of a different species 

 from those of Finkler and Prior, of Miller, and of the species 

 described above as found in noma, it does not follow that 

 they are identical with those cultivated by Deneke or by 

 myself from the mouth, from a case of noma, and (as I shall 

 hereafter mention) from a monkey that had been subjected 

 to certain definite experiments. And it seems to me that 

 Koch and his adherents go too far in trying to make 

 out first, that the comma-bacilli belong exclusively to 

 Asiatic cholera, and then, after this had been disproved, 

 that they differ from all other comma-bacilli in mode of 



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