1879.] 



Dr. G. Thin. Anatomy of the Skin. 



251 



I. " On some Points connected with the Anatomy of the Skin." 

 By George Thin, M.D. Communicated by Professor 

 Huxley, Sec. R.S. Received November 25, 1878. 



[Plates 2 and 3.] 



Rollett, in 1858,* in a memoir on connective tissue, described the 

 results of an elaborate investigation into the structure of the corium. 

 Microscopic examination of leather, and of skin tanned by himself, 

 had shown him that the connective tissue bundles of the corium are 

 made up of smaller divisions, and that these latter are again made up 

 of the previously known minute connective tissue fibrillas, which are 

 so small that their diameter can only be approximately estimated at 

 0*0002 to 0*0003 millim. Prom the connective tissue bundles of the 

 skin of the ox, " treated by lime or baryta water, there can," he states, 

 " be isolated from each bundle a number of component elements which 

 have a considerably larger diameter than the minute fibres known as 

 connective tissue fibrilles." These elements have, he remarks, in the 

 ox a thickness of 0*003 — 0*006 millim., and he proposes to call them 

 connective tissue fibres (Bindegewebsfaser). In a plate attached to 

 his memoir the bundles and their divisions are shown in a very dis- 

 tinct manner. 



This observation of Rollett's has not arrested the attention of 

 anatomists to the degree which might have been expected, and seems, 

 indeed, to have been to a great extent neglected. Two of the latest 

 standard works may be quoted in illustration of this remark. W. 

 Krause, in a volume on " General and Microscopic Anatomy," pub- 

 lished in 1876, describes the tissue of the corium proper as being com- 

 posed of "a network of strong bundles of connective tissue closely 

 interwoven, the bundles being partly cylindrical, partly flattened." 

 There is nothing said about the subdivision of the bundles, as described 

 by Rollett. 



The same author, in his chapter on connective tissue, states, " that 

 the ground substance of fibrous tissue consists of closely-packed, very 

 fine, round connective tissue fibrilla?, measuring 0002 — 0*002 millim." 

 The larger of these measurements is inapplicable to the fibrilla of 

 Rollett, and is so near that of the subdivision or "fibre" of that 

 author, that it is evident that Krause does not recognise the distinc- 

 tion between the fibre and the fibrilla established by the former his- 

 tologist. 



In Quain's "Anatomy "f it is stated, "that the corium is made up 

 of an exceedingly strong and tough framework of interlaced connec- 

 tive tissue fibres with blood-vessels and lymphatics. The fibres are 



* " Sitzungsbericht der Kaiserlichen Akadaniie der Wissensehaften," vol. xxx. 



f Eighth edition, edited by Dr. Sharpey, Dr. A. Thomson, and Mr. S chafer ; 

 p. 213, vol. ii. 



T 2 



