160 



DR. C. F. SONNXAG ON THE 



increase in size from before backwards and from without inwai-ds, 

 and they are discrete, so there is no overlapping. They extend 

 beyond the vallate papill*, and there is a sharp line of demar- 

 cation between them and the lymphoid tissue at the base. 



On the base of the tongue there are many lymphoid nodules, 

 some of which have central apertures, and there is a line, convex 

 backwards, separating the papillary and lymphoid areas. 



Text-figure 10. 



The tongue. A : inferior surface. B : dorsum. C : lateral view. 



No lytta is present as Rapp showed (10). 



The inferior surface has a narrow papillary border. There is a 

 fine mesial notch, but no mesial ridge, sulcus, nor frenum. The 

 surface is marked by fine horizontnl ridges, but there are no 

 plicfe fimbriatfe. The papillary border forms thick masses at 

 either side of the apex. 



The tongue, according to Rapp, is mechanical rather than 

 gustatory in function. 



