192 VEGETABLE PARASITES. 



the epithelium and the fungus continue to grow, the more they 

 will run together and form a continuous layer, which covers the 

 whole mucous membrane and its cavities (Muguet confluent), 

 formed partly through the natural combination of the epithelial 

 cells, partly through the entanglement of the filaments of the 

 fungus amongst themselves and with the epithelial cells. Epi- 

 thelial cells are met with mixed with cross filaments, sometimes 

 covered with adhering spores, sometimes not, exhibiting, more- 

 over, a more or less thick mucus, together with molecular granu- 

 lations. Some filaments are seen broken up. A little practice 

 will enable the operator to recognise the fungus without the 

 microscope, provided it exists in considerable quantity. The 

 mucous membrane underneath is seen to glimmer through if the 

 epithelium possesses its natural density and transparency. The 

 surface becomes less transparent and white when the epithelium 

 thickens, and is macerated by heterogeneous liquids (milk- or 

 pearl-white colouring of the infected spots). This milky colour 

 passes into a yellowish or green tint when the growth of the 

 fungus and the plentiful formation of spores takes its uninter- 

 rupted course. A similar observation has been made with regard 

 to the spores of other fungi. The other colours of the soor- 

 layer will be entered into more especially when we are speaking 

 of the colour of the thrush itself, and it will suffice to remark 

 here that the white colour is more particularly attributable to the 

 granulations in children in private families whose mouths are 

 kept carefully clean. 



The layers of the fungus have the following position : Upon the 

 mucous membrane is found a dense layer of epithelium ; the 

 fungus covers entirely the edges of the epithelial cells on their 

 free side ; the aphthous layers (soor-plaques) thus formed are 

 soft ; they grow to a larger extent, and the more rapidly, the 

 more lacerated the tongue is, and the more numerous and larger 

 the papillae of the tongue are. The firmer the epithelium is 

 seated on the tongue, the deeper they penetrate into the cells, 

 which usually contain the roots of the fungus, whilst the filaments 

 and branches make their way to the open air, the firmer will be 

 their original footing. But if the epithelial layer becomes loose, 

 after a little time, the fungus, together with the normally 

 loosened epithelium, separates in smaller or larger membranous 

 patches. This separation seems to proceed quicker when the re- 

 newed growth and separation of the epithelium itself is unna- 



