XL] BACILLUS: PATHOGENIC FORMS. 181 



mouth of normal persons (Lewis) ; in old cheese (Denike). 

 The comma-bacilli found by Finkler and Prior in old stools 

 of cholera nostras differ in size and mode of growth from 

 Koch's comma-bacilli. So do those found in diarrhoea due to 

 other causes. But some species in the fluids of the mouth are 

 identical with Koch's comma-bacilli in their mode of growth. 

 The small straight bacilli above described are probably 

 identical with those mentioned by Emmerich, and which 

 are regarded by this observer as the true cause of cholera. 

 On guinea-pigs they act very poisonously. 



Koch has shown that if guinea-pigs be kept for twenty-four hours 

 without food, then 5 cc. of a 5 per. cent, solution of sodic carbonate, and 

 after twenty minute*, 10 cc. of a broth cultivation of choleraic comma- 

 bacilli be injected into the stomach, and immediately after this I cc. 

 of (German) tincture of opium for each 200 grammes weight of the 

 animal is injected into the peritoneal cavity, the majority of these 

 animals die after a day and a half to three days. The small and large 

 intestine are found distended by, and filled with a clear fluid containing 

 numerously the choleraic comma-bacilli. Experiments of this nature 

 have no bearing whatever on the question of the causal relation of the 

 comma-bacilli to cholera in man, for the following reasons : 



(1) It is quite gratuitous to consider the disease from which those 

 animals die as cholera, for during life they do not show any of the 

 special symptoms characterising cholera. 



(2) Koch himself has proved by numerous experiments that guinea- 

 pigs treated in the above manner, but omitting the injection of opium 

 tincture into the peritoneum, do not become ill at all, although even 

 twenty hours after the introduction of the comma-bacilli, the stomach and 

 small and large intestine contain them numerously in a living state, as 

 is proved by the successful plate cultivations made by Koch himself 

 from the contents of these organs. 



(3) Death of the animals has been produced after precisely the same 

 method by Finkler's comma-bacilli, and even by Denike's cheese 

 comma-bacilli. 



(4) Death does not ensue unless tincture not watery solution of 

 opium be injected into the peritoneal cavity. 



From all this it follows that the choleraic comma-bacilli are powerless 

 to produce disease in guinea-pigs, even if present in the small and large 

 intestine in a living state ; and that a previous pathological state of the 

 intestine, such for instance as is produced by the injection into the 

 peritoneal cavity of considerable quantities of tincture of opium, 

 enables the comma-bacilli to undergo multiplication. 



