PROCEEDINGS 



OF 



THE ROYAL SOCIETY. 



1846. No. 65. 



Ma^ 7, 1846. 



The MARQUIS OF NORTHAMPTON, President, in the Chair. 

 W. G. Armstrong, Esq., was elected a Fellow of the Society. 



" On the Anatomy and Physiology of the Vascular Fringes in 

 Joints, and the Sheaths of Tendons." By George Rainey, Esq., 

 M.R.C.S. Communicated by John Simon, Esq., F.R.S., Assistant- 

 Surgeon to the King's College Hospital, and Demonstrator of Ana- 

 tomy in King's College, London. 



It has been generally believed that the folds of synovial mem- 

 brane which project into the articular cavities in the form of fringes, 

 contain merely globules of fat, and are subservient only to the me- 

 chanical offices of filling up spaces that would otherwise be left 

 vacant during the movements of the joints. By a careful examina- 

 tion of their real structure with the aid of the microscope, the au- 

 thor has found that they present an arrangement of vessels quite 

 peculiar to themselves, and bearing no resemblance whatever to 

 that of the vessels which secrete fat ; together with an epithelium, 

 remarkable by its form and disposition, and characteristic of organs 

 endowed with the function of a special secretion. He has traced 

 the presence of these synovial fringes in all cavities which contain 

 synovia ; that is to say, not only in the joints, but also in the sheaths 

 of tendons, and in the bursse mucosae. When well-injected, they are 

 seen, under the microscope, to consist of two parts ; namely, a con- 

 volution of blood-vessels, and an investing epithelium. These con- 

 voluted vessels do not enclose, by their anastomoses, spaces like 

 those capillaries which secrete fat, and whicii are of a much smaller 

 size than the former ; and the epithelial investments, besides en- 

 closing separately each packet of convoluted vessels, sends off* from 

 each tubular sheath secondary processes of various shapes, into 

 which no blood-vessels enter. The lamina itself, forming these 

 folds and processes, consists of a very thin membrane studded with 

 flattish oval cells, a little larger than blood-corpuscles, but destitute 

 of nucleus or nucleoli ; presenting none of the characters of tes- 



