158 



THE CARTILAGINOUS TISSUE. 



cartilage corpuscles, containing nucleii and nucleoli, situ- 

 ated in an amorphous substance from which arises the cyto- 

 blasts or germinal particles forming the cells. The cells 

 are found to vary in their size, shape, and number, accord- 

 ing to the cartilages examined. Those of the ribs measure 

 FIG. 29. from 1-650 to 1-430 of an 



inch in diameter, while 

 in the cartilages of the 

 joints they are from 

 1-1300 to 1-900 of an 

 inch. Their shape is 

 ovoidal, round or lenti- 

 cular and notched. The 

 cell cartilage is distin- 

 guished by a substance 

 called chondrin, which 

 resembles gelatin, but 

 requires a longer boil- 

 ing for its solution. It hardens on cooling, and looks like 

 glue. It is not precipitated by tannic acid, in which it 

 differs from gelatin. Acetic acid, alum, acetate of lead, 

 and proto-sulphate of iron, precipitate chondrin, but have 

 no effect on gelatin. .Cartilage is supposed to be nourished 

 by the agency of its cell, those nearest the blood vessels 

 take the nutritive materials and hand it over to the next 

 series, and those to the next, and so in regular succession 

 till the whole is supplied. 



The functions of cartilages are to supply the place of 

 bone in some parts, and to connect and facilitate their mo- 

 tions in others. Cartilages are accidentally developed in 

 various parts of the body, as in the lungs, arteries, semi- 

 lunar valves, pleurge, coverings of spleen, testicles, ureters, 

 vagina, and in the substance of some organs, as the ovaries, 



FIG. 29 represents a cylinder of bone filled with cartilage corpuscles ; 6 c 

 represents several lamina of bone and unossified cartilage corpuscles ; d rep- 

 resents the process of ossification as complete, and the opening in the centre 

 as the Haversian canal of the^ossicle j e shows the interosseous space filled 

 with bony matter. 



