

CARTILAGE. 119 



another, and to the cell wall, or intercellular sub- 

 stance in the two tissues respectively, will be at once 

 understood if we call to mind the fact that each mass 

 of bioplasm produces upon its surface the tissue, be it 

 termed matrix, cell wall, or intercellular substance. This 

 tissue accumulates between the several masses of bio- 

 plasm. Now, even in epithelial textures, at an early 

 period of formation, the formed material does exist as 

 a continuous mass, which occupies the intervals be- 

 tween the several masses of bioplasm, and exhibits an 

 arrangement similar to that which is met with in adult 

 cartilage and fibrous tissue ; but as the growth of the 

 epithelium advances, the portion of formed material 

 belonging to each mass separates from its neighbours, 

 and thus " cells " of epithelium result. I have 

 figured a good specimen of this in " Protoplasm." See 

 also the second part of the " Physiological Anatomy." 

 The main difference, therefore, between adult cartilage 

 and fully formed epithelium is at once perceived, for 

 in the cartilage each " cell" is not marked off from 

 its neighbours, but is represented by a mass of bio- 

 plasm, including a proportion of the so-called matrix, 

 or intercellular substance around it, while in epithe- 

 lium each separate bioplast is invested with its layer 

 or capsule of formed matrix. Some forms of carti- 

 lage are, however, really composed of " cells," which 

 may be separated from one another just as in epithe- 

 lium. The distinction, therefore, which has been 

 drawn between different tissues, based upon the pre- 

 sence or absence of "cells" in the fully- formed tex- 

 ture, cannot be sustained, and the classification as epi- 

 thelial and connective tissues breaks down. 



169. Cartilage. I propose now to refer to cartilage, 

 a tissue which possesses many points of interest, and 

 which has formed the subject of many an anatomical 

 controversy. It is generally stated that cartilage is com- 

 posed of "cells " and " intercellular substance," and that 

 the latter is formed and deposited in the intervals be- 



