126 THE BLADDER AND URETERS, BY HEINRICH OBERSTEINER. 



its elements; corresponding nearly to each other in size (being 

 about 0'03 of a millimeter in their longest diameter) the cells 

 present a conical form, with their broad convex bases directed 

 towards the surface. The apices directed towards the deeper 

 tissues are prolonged into an unbranched and often varicose 

 process of various length, reminding the observer of the epithe- 

 lial cells of the nasal mucous membrane. 



It is not easy to ascertain the further course of those 

 peduncles or processes which penetrate into the deepest 

 layers of the epithelial cells, yet it appears highly probable 

 that they establish a connection between the cells and the 

 most superficial layers of the connective tissue immediately 

 subjacent to the vesical epithelium, joining either with the 

 connective tissue or with the nervous elements. In favour of 

 this view is the fact that, however carefully the cells may be 

 isolated, the processes never end in a point, but always give 

 the impression of not having been obtained in their integrity ; 

 or, in other words, of having been abruptly broken off. An ad- 

 ditional argument is derived from the fact, that, after the epi- 

 thelium has been detached, fine fibres, curled at their extremities, 

 and of equal size with the processes of the cells, project from 

 the surface of the connective tissue, and occasionally it may 

 even happen that appearances are presented indicating an 

 immediate connection between the two structures. 



The frequently discussed question of the origin of epithelial 

 cells from subjacent connective tissue may obtain some elucida- 

 tion from these relations. 



The deepest or most external layer of the epithelium 

 (fig. 164, c 3) is composed of rather irregular oval cells, which 

 are frequently elongated towards the surface, their extremities 

 being intercalated between the conical ends of the cells of the 

 above-mentioned layer. 



II. THE CONNECTIVE-TISSUE LAYERS. A layer of very dense, 

 finely fibrous connective tissue, containing numerous nuclei, and 

 of about 0'02 of a millimeter in thickness, lies immediately 

 beneath the epithelium, and is sharply differentiated from 

 external layer that contains fewer connective-tissue corpusclt 

 and thicker bundles of fibrillse, and varies from 0'8 to 1*5 



