VIBRIONES 385 



with a serous fluid which contains innumerable spirilla. The blood 

 also contains many spirilla. The mucosa of the intestines is pale and 

 the intestinal contents are liquid and likewise contain the organism. 

 Guinea-pigs also generally succumb to subcutaneous infection within 

 twenty-four hours. A hemorrhagic edema is formed at the place of 

 inoculation, and the fluid and blood show enormous numbers of 

 vibriones. The vibrio of Asiatic cholera, on the contrary, in sub- 

 cutaneous or intravascular injection never produces a rapidly fatal 

 septicemia in these animals, which are so susceptible to the spirillum 

 of Metchnikoff. In spite of their great morphologic and cultural 

 similarities the two organisms are by no means identical. They are 

 very different in their pathogenicity and animals cannot be immunized 

 with one species against the other. 



Fio. 155 



A characteristic series of cholera cultures in gelatin; from right to left, one, two, three, four, 

 and six days' growth. (Dunham.) 



Vibrio of Asiatic Cholera. This organism was discovered by Robert 

 Koch in India. Asiatic cholera is a disease of man and does not 

 naturally occur among the lower animals. The disease is endemic 

 in India, but has spread from there on various occasions into Europe, 

 America, and other countries. It is one of the most fatal epidemics of 

 mankind, and has a very high mortality. The great similarity between 

 the spirillum of Asiatic cholera and the Vibrio Metchnikovi has already 

 been referred to above; it also closely resembles several other spirilla, 

 which will be described later. 



The cholera vibrio, also called the comma bacillus of Koch, is a 

 curved organism, and in artificial cultures often forms longer spirals 

 25 



