22 



EPITHELIUM 



[CH. III. 



It consists of three or four layers of large cells, the most typical of 

 which are pear-shaped (fig. 31). 



FIG. 27. Columnar epithelium cells of the rabbit's 

 intestine. The cells have been isolated after 

 maceration in very weak chromic acid. The 

 cells are much vacuolated, arid one of them 

 has a fat globule near its attached end. The 

 striated border (sir.") is well seen, and the 

 bright disc separating it from the cell proto- 

 plasm, n, nucleus with intra-nuclear net- 

 work; a, a thinned-out winglike projection 

 of the cell which probably fitted between two 

 adjacent cells. (Schafer.) 



FIG. 28. Vertical section of an intestinal villus 

 of a cat. a, The striated border of the epi- 

 thelium ; b, columnar epithelium ; c, goblet 

 cells ; d, central lymph-vessel ; c, unstriped 

 muscular fibres ; /, adenoid stroma of the 

 villus in which are contained lymph-cor- 

 puscles. (Klein.) 



FIG. 29. A row of columnar cells from the 

 rabbit's intestine. Smaller cells are seen 

 between the epithelium cells ; these are 

 lymph-corpuscles. (Schiifer.) 



FIG. 30. Goblet cells. (Klein.) 



FIG. 31. Epithelium of the bladder, a, One of the cells of 

 the first row ; b, a cell of the second row ; c, cells in situ, 

 of first, second, and deepest layers. (Obersteiner.) 



&. Stratified epithelium. Here the cells are arranged in numerous 

 layers. It is found composing the epidermis, and the linings of the 



