352 CLINICAL BACTERIOLOGY. 



situations pavement epithelium is present, and it has been 

 assumed that the thrush-fungus is capable of proliferating 

 only upon mucous membrane covered with such epithelium. 

 The thrush-fungus is not rarely encountered in the vagina 

 of pregnant women, which likewise is lined with pavement 

 epithelium. It occurs, however, also upon mucous mem- 

 branes lined with other kinds of epithelium as, for instance, 

 that of the stomach, the posterior surface of the epiglottis, 

 the deeper portions of the respiratory tract, although but 

 seldom in all of .these situations. The thrush-fungus has 

 been demonstrated repeatedly in bronchopneumonic foci, 

 and in numerous instances upon the mammary glands and 

 mammillary areolae of nursing women whose children suf- 

 fered from thrush, and in one instance in encephalitic sup- 

 purative foci in a child suffering from thrush. 



Course of Thrush. The thrush-fungus penetrates the 

 uninjured epithelial surface, and develops beneath the up- 

 permost layer of epithelium, within the deeper portions of 

 the mucosa. Only rarely does it invade the submucosa. 

 The abundant fungous vegetation raises the upper epithelial 

 layer, and gradually separates it from the connection with 

 the lower layers necessary for its nutrition, so that it under- 

 goes necrosis and exfoliation. The thrush-membrane is 

 then exposed to view. The thrush-proliferation usually gives 

 rise to mild local -irritative manifestations. The mucous 

 membrane generally appears somewhat altered at the site of 

 the thrush-deposits. It is dark red, slightly swollen, dry, 

 and distinctly sensitive to touch. The signs of an actual 

 inflammation are, however, not discoverable microscopi- 

 cally. It has been assumed that the thrush-fungus can 

 find lodgment only upon mucous membranes the seat of 

 catarrhal inflammation. This, however, does not appear 

 to be correct, but the slight evidences of irritation may 

 really be the result of the purely mechanical action of the 

 fungous vegetation. The saliva of patients suffering from 

 thrush invariably has an acid reaction. There is no sug- 

 gestion of chemic activity on the part of the thrush-fungus, 

 of any production of toxin. There is an absence of fever 

 and, in fact, of all constitutional manifestations. The 

 symptoms are of a purely local nature. The fungous 

 proliferation may become dangerous only when, by reason 

 of especially luxurious development, it obstructs the 

 esophagus or the larynx ; and, further, in small children, 



