STRUCTURE OF SEROUS MEMBRANES. 437 



the fibres of the areolar texture, or with elastic filaments, or 

 with the nuclei of the capillary vessels of the subserous 

 texture, or with paler, ovoidal, somewhat indistinct cells, 

 scattered throughout that texture, and which appear to be 

 connected with the common areolar fibres. 



These flattened ribbon-shaped scales, and bright crystalline 

 nuclei, which form the germinal or basement membrane of 

 the serous coat appear to be identical with the objects de- 

 scribed by Valentin,* Pappenheim,t and Henle,J and named 

 by the latter nucleated fibres. 



In inflamed or aged serous membranes, I have found it 

 impossible to detect this membrane, or even the superimposed 

 scales. The germinal membrane in such instances appears to 

 break up into areolar texture, and to assimilate itself to the 

 bursae mucosse, or the ordinary enlarged areolae of the areolar 

 texture. 



If these germinal centres be the sources of all the scales 

 of the superficial layer, each centre being the source of the 

 scales of its own compartment, then the matter necessary 

 for the formation of these during their development must 

 pass from the capillary vessels to each of the centres acted on 

 by forces whose centres of action are the germinal spots ; 

 each of the scales, after being detached from its parent centre, 

 deriving its nourishment by its own inherent powers. 



I have been in the habit of considering the highly vascular 

 fringes and processes of the synovial membranes as more 

 active in the formation of epithelium, and therefore more 

 closely allied to the secreting organs, than other portions of 

 these membranes. If this be the case, Clopton Havers was 

 not mistaken in his ideas regarding the functions of these 



* Valentin, Repertorium, 1838. 

 t Pappenheim, Zur Kentniss der Verdauung, 1839. 



+ Henle, Anatomie Allgemeine. 

 Clopton Havers, Osteologia Nova, 1691. 



