SPIRILLA RESEMBLING CHOLERA. 335 



medium rich in peptone produces the same rose color 

 observed in cholera cultivations. 



The organism is pathogenic for animals, but not for 

 man. PfeifFer has shown that chickens, pigeons, and 

 guinea-pigs are highly susceptible animals. The birds 

 when inoculated under the skin generally die pigeons 

 always. W. Rindfleish has pointed out that this positive 

 fatal outcome of the introduction of the spirillum into 

 pigeons makes it a valuable diagnostic point for the 

 differentiation of this spirillum from that of cholera. 

 According to his researches, the simple subcutaneous in- 

 jection of the most virulent cholera cultures is never 

 fatal to pigeons. The birds only die when the injections 

 are made into the muscles in such a manner that the 

 muscular tissue is injured and becomes a locus minoris 

 resistentice. When guinea-pigs are treated according to 

 the method of Koch for the inoculation of cholera, the 

 temperature of the animal rises for a short time, then 

 abruptly falls to 33 C. or less. Death follows in twenty 

 to twenty-four hours. A distinct inflammation of the 

 intestine, with exudate and numerous spirilla, may be 

 found. The spirilla can also be found in the heart's 

 blood and in the organs of such guinea-pigs. When the 

 bacilli are introduced by subcutaneous inoculation, the 

 autopsy shows a bloody edema and a superficial necrosis 

 of the tissues. 



In the blood and all the organs of pigeons and young 

 chickens the organisms can be found in such large num- 

 bers that Pfeiffer has suggested the term " vibrionensep- 

 ticsemie" for the condition. In the intestines very few 

 alterations are noticeable, and very few spirilla can be 

 found. 



Gamaleia has shown that pigeons and guinea-pigs can 

 be made immune by inoculating them with cultures ster- 

 ilized for a time at a temperature of 100 C. Mice and 

 rabbits are immune except to very large doses. 



Spirillum Berolinensis. This organism (Fig. 91), 

 which was discovered by Neisser in the summer of 1893, 



