102 THE CONNECTIVE TISSUES, BY A. ROLLETT. 



dition, and examined in thin sections or laminae with very 

 high powers, often presents a thoroughly homogeneous appear- 

 ance. But it also happens that in recent and very transparent 

 cartilages, especially in those in which the cells lie close toge- 

 ther as, for instance, in the earlier-mentioned examples of 

 cartilage from the Frog and Triton the cells are apparently 

 surrounded by clear rings of equal breadth ; and that the small 

 trabeculse extending between the adjoining cells only repre- 

 sent the circular layers investing these cells. In the older 

 cartilages of various animals and of man there may also fre- 

 quently, but not always, be seen a similar circular area which 

 sometimes appears as though composed of several concentric 

 rings. According to Max Schultze, this appearance is very 

 beautifully exhibited in the cartilage of the Myxine. These 

 rings represent the transverse section of the successive shells 

 deposited around the cartilage cells, constituting the so-called 

 membrane of the cartilage cell, or cartilage capsules of authors. 

 We shall learn their significance hereafter. By the application 

 of certain reagents, as, for instance, diluted sulphuric acid 

 and chromic acid,* or a mixture of water, nitric acid, and chlo- 

 rate of potash, or by digestion in water, at a temperature of 

 from 35 to 40C.f (95 to 104 F.) (in which case the addition 

 of acids, in order to convert the connective tissue as usual at 

 a lower temperature into gelatine, operates very effectually) 

 the matrix of the cartilage, however homogeneous it may 

 appear to be in the fresh condition, may be split up so com- 

 pletely into a number of layers arranged concentrically around 

 the cells, that nothing remains besides them ; and, indeed, in 

 more fully developed cartilages a series of precisely similar 

 shells succeed that which immediately surrounds the cell ; or 

 there may appear two or more closely approximated cells, with 

 their primary capsules enclosed in secondary capsules, and groups 

 of the latter again enclosed in still larger ones. It is only in 

 cartilages with sparingly distributed cells that a portion of the 

 firm matrix at a great distance from the cells surrounded with 



* Fiirstenburg, Miiller's Archiv, 1857, p. 1. 

 t Heidenhain, loc. cit., pp. 23 and 25. 



