GASTEIO MIORO-ORaANISMS 245 



coccus jpneuraonicB, and also the Bacillus pyocyaneus, amongst 

 others. 



The Stomach 



Micro-organisms of the stomacli. — By examining vomited 

 matters, or by washing out the stomach, some micro- 

 organisms are found in its contents, which are in part de- 

 rived from the air, having made their way into the region of 

 the pharynx by means of respiration, and passed on thence 

 into the stomach by the act of swallowing ; and similarly 

 micro-organisms can be conveyed into the stomach along 

 with water or articles of food, or also from the mouth by 

 means of the saliva. Neither the surface of the mucous 

 membrane lining the stomach, nor its contents, forms, as a 

 rule, a favourable nidus for the various micro-organisms, 

 since the acid contained in it has a destructive action on 

 most of them. Other microbes, on the contrary, resist the 

 acid of the gastric juice, and are also capable of thriving 

 when but little oxygen has access, and hence can grow 

 and maintain themselves for a considerable time in the 

 stomach. 



Abelous found certain microbes which are normally 

 present in the stomach. To these gastric bacteria be- 

 long the Sarcina ventriculi, Bacterium lactis aerogenes, 

 Bacillus pyocyaneus a, Bacillus subtilis. Bacillus amylohacter, 

 Bacillus megaterium, Bacillus mycoides, and Vibrio rugula. 

 Besides these, other bacteria have been described by this 

 author which are not yet thoroughly known, but amongst 

 which bacilli preponderate. Before Abelous, De Bary had 

 subjected the contents of the stomach to an investigation, 

 and, in addition to different bacteria, discovered the O'idiimi 

 lactis and the Leptothrix buccalis. 



It happens in many cases that the acid constituent of 

 the contents of the stomach is reduced to a minimum, or 

 the reaction may even change to alkalinity, so rendering 



