392 PROCEEDINGS OF THE CANADIAN INSTITUTE. 



ficial stratum is reached, where they are much more elongated than 

 elsewhere, and hei*e they evidence the possession of a cell membrane. 



At the lower half of the layers formed of columnar cells, are 

 structures which when viewed carelessly appear as nuclei of the cells. 

 Yet they are everywhere quite distinct from these in that they are 

 smaller and they take on a deeper staining in Bismarck brown. Pro- 

 fuse in the lower columnar layers, they are sparsely distributed 

 towards the layers formed of cubical or flattened cells. They are 

 about the size of the nucleoli of the surrounding cells. Each, how- 

 ever, contains a nucleolar body and is provided with a short, delicate 

 process directed towards the deeper stratum. As they stain more 

 deeply than the nuclei and nucleoli of the surrounding cells, I must 

 regard them as separate structures. They are most favorably seen 

 in the lips. They may be regarded as the terminal free nerve end- 

 ings to the fibrils which come from the deeper coat below. 



Besides the structures described, there are in the epithelial layer 

 two others which merit special description. The first of these is the 

 1 slime cell.' It is present in all portions of the epithelial stratum, 

 and in accordance with this distribution it presents various shapes. 

 On the surface it is of flask shape, the long neck of which is thrust 

 out between the cuticular cells. (Fig. 1). The body of the flask 

 is rounded and rests on the layers of flattened cells. The contents 

 of the flask project beyond the superficial border in the form of a 

 plug. No separation can be seen in ordinary preparations between 

 its mucigenous and its protoplasmic portions. Such can only be 

 observed in osmic acid specimens. The rounded body is not con- 

 tinued downwards into fine processes, as is usual in beaker cells. 

 The nucleus is seen with the aid of osmic acid, and is usually sur- 

 rounded by a clearly defined protoplasmic stroma or reticulation, 

 which stains vividly in Bismarck brown or hematoxylon. The reticu- 

 lation is observable even in the neck of the cell. 



Three, most frequently four, cuticular cells separate two neigh- 

 bouring slime cells. 



They take an intense brown color in B ; smarck brown and a 

 deep purple color in Kleinenberg's hematoxylon, even when the sur- 

 rounding cells are little acted on. They are of oval shape in the 

 deeper epithelial layers and their long axis is generally perpendicular 

 to the surface. They are placed sometimes horizontally in the layers 

 formed of flattened epithelium. Their reticulation is wider meshed, 



