OIDIUM ALBICANS. 209 



original disease that depends upon a disordered condition of the 

 blood (scorbutus, morbus maculosus Werlhoffii, &c.), or a more 

 copious ulceration. The cure of thrush will remain an impossi- 

 bility as long as the remedial agents do not succeed in removing 

 the original disease and in changing the soil on which the fungi 

 thrive. 



After having thus studied this disease in all its forms, we now 

 proceed to speak of the differential diagnosis. Following the 

 very able historical and physical description by Berg, and viewing 

 thrush and aphtha as synonymous, I give the differential diag- 

 nosis, with some modifications, according to Eeubold : 



1. Stomatitis vesicularis. Distinct little vesicles, often arranged 

 in regular groups, are perceived on the surface, at the top and 

 on the edges of the tongue, especially in older infants, which 

 sometimes heal rapidly, and sometimes pass into pustules or ulcera- 

 tions. These vesicles, when they are still small and filled with a 

 whitish-gray matter without reddening the surrounding mucous 

 membrane, are not easily made out without the aid of the micro- 

 scope. They are, however, easily distinguished when the vesicles 

 are a little larger and surrounded by an inflamed ring, and filled 

 with a larger mass of a clear transparent liquid, when they spring 

 up discretely, or burst after a little while, presenting an ulcerated 

 mass, covered with a dirty yellowish secretion. When the thrush 

 lasts very long it becomes accompanied by ulcers, although the 

 fungus is found to grow secondarily even in the colon and on 

 diphtheritical exudations, which resemble it to some extent in 

 colour. The thrush resembles at first crummy, gritty bits of 

 cheese, or patches of coagulated milk, which look like the slough 

 of ulcers ; the fungus itself supplies, however, the distinctive diag- 

 nosis. 



2. Certain affections of the epithelium of the mucous membrane, 

 especially epithelial accumulations. They are very much like the 

 patches of thrush. The chief distinction is found in a thicker 

 and a shining layer of epithelium, and in their remaining sta- 

 tionary and unaltered for from four to six weeks, until they dis- 

 appear at last. They are often met with, but always ill an 

 isolated state, and on the middle line of the hard palate, towards 

 the front of the alveolar processes. They are likely to occur 

 sometimes to a larger extent and in a higher degree, and I 

 believe that the Stomatitis morbillosa of Reubold and the Pityriasis 



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