INFECTIOUS DISEASES AND MICROBES, ETC. 229 



therefore no proof of the assertion that it is a result 

 of the disease, (c) The means used to introduce 

 the comma bacillus into, and those used to lessen 

 the peristalsis of, the small intestine of the guinea- 

 pig, cannot be regarded as causing appearances like 

 those of Asiatic cholera, or as causing the death of 

 the animal, far less a mortality of over 60 per cent. 

 (d) Pure cultivations of the microbe are pathogenic 

 to the guinea-pig, (e) The contents of the ileum 

 from those animals killed by injections of pure 

 cultivations of the bacilli act in the same manner 

 as pure cultivations of that microbe. (/) The 

 microbe multiplies in the small intestine of the 

 animal, and there is associated therewith changes 

 similar to those in man in Asiatic cholera, (g) As 

 there are conditions which favour the passage alive 

 of the comma bacillus through the stomach of the 

 guinea-pig, and also conditions which favour its 

 multiplication in the small intestine of that animal; 

 so in man, as there cannot be a doubt that the 

 microbe finds conditions favourable to its multipli- 

 cation in his small intestine, it must have found 

 conditions favourable to its entrance alive through, 

 in all probability, the mouth and the stomach 

 (Macleod and Milles). 



The comma bacillus grows in neutral bouillon, 

 gelatine, agar-agar, milk, and on steamed potatoes. 

 It grows best if the medium is slightly alkaline, 

 and at a temperature ranging from 16 to 40 C. 

 On gelatine plates the colonies (Fig. 44) are evident 

 in about twenty-four hours, and appear, under a 

 low power, as small, somewhat irregular pale masses. 



