486 BACTERIOLOGY. 



pose of arresting peristalsis and permitting the bac- 

 teria to remain in the stomach and upper part of the 

 duodenum for as long a time as possible, the animal was 

 to receive, immediately following the injection of the 

 culture, an intraperitoneal injection, by means of a 

 hypodermic syringe, of 1 c.c. of tincture of opium for 

 eacli 200 grammes of its body-weight. Shortly after 

 this last injection deep narcosis sets in and lasts from 

 a half to one hour, after which the animal is as lively 

 as ever. Of 35 guinea-pigs inoculated in this way by 

 Koch, 30 died of an affection that was, in general, very 

 similar to Asiatic cholera as seen in man. 



The condition of those animals before death is de- 

 scribed as follows : twenty-four hours after the opera- 

 tion the animal appears unwell ; there is loss of appetite, 

 and the animal remains quiet in its cage. On the fol- 

 lowing day a paralytic condition of the hind extremities 

 appears, which, as the day wears on, becomes more 

 pronounced ; the animal lies quite flat upon its abdomen 

 or on its side, with legs extended ; respiration is weak 

 and prolonged, and the pulsations of the heart are hardly 

 perceptible ; the head and extremities are cold, and the 

 body-temperature is frequently subnormal. The ani- 

 mal usually dies after remaining in this condition for a 

 few hours. 



At autopsy the small intestine is found deeply in- 

 jected and filled with flocculent, colorless fluid. The 

 stomach and intestines do not contain solid masses, but 

 fluid ; when diarrhoea does not occur, firm scybala may 

 be detected in the rectum. Both by microscopic exam- 

 ination and by culture methods the organisms are 

 found present in the small intestine in practically pure 

 culture. 



