EPITHELIAL AND ENDOTHELIAL TISSUE. 



323 



the rim between the feet of the epithelia and the neighboring 

 fibers of connective tissue j or it is indirect, by means of an inter- 

 vening basement layer. The latter is probably pervaded by a 

 bioplasson reticulnm (I have seen it in Bowman's layer of the 

 cornea of the cat), which inosculates with that of the epithelia. 

 Basement layers, however, are not constant formations; they are 

 sometimes broad, sometimes narrow, and sometimes altogether 

 absent, in one and the same organ in different persons. The 

 outer surface of the basement membrane, in many instances, is 

 found to be covered by a layer of flat, polyhedral bodies discov- 

 ered by V. Czerny, by means of silver-staining. These bodies are 

 classed among endothelia. 



FIG. 139. STRATIFIED EPITHELIUM OF THE SKIN, COVERING A MYXO- 



FIBROMA ON THE RlGHT SHOULDER. VERTICAL SECTION. 



F, flat epithelia ; Cu, cuboidal epithelia ; Co, columnar epithelia, all the three composing 

 the epithelial layer, E , D, derma of skin, composed of vascularized connective tissue, C. 

 Magnified 600 diameters. 



Termination of Nerves. Since Cohnheim's researches, we know that the 

 finest axis-fibrillaa of the nerves terminate in the epithelial layers. The ter- 

 mination was described by some observers as a plexus between the epithelia, 

 while others (Pnliger, Flemming) claim that the axis-fibrillae penetrate the 

 body of the epithelium, and may terminate in its nucleolus. My own obser- 

 vations enable me to state that the axis-fibrillae which, in specimens stained 



