256 SKELETON. 



CHAPTER II. 



OF THE FIBRO OR LIGAMENTO-CART1LAGINOUS SYSTEM. 



THIS set of organs (Systeme fibro-cartilagineux) has been 

 placed -by anatomists, indiscriminately in the cartilaginous or 

 in the ligamentous system, in consequence of its participating 

 in the characters of both; it, however, from its importance, 

 should have a distinct position. There are three varieties of 

 this system. The first presents itself in a membranous state, 

 and is represented by the external ear, by the alas of the nose, 

 by the cartilage of the eye-lids, and by the trachea. The se- 

 cond is represented by the inter-articular cartilages of the move- 

 able articulations, as of the knee, the wrist, lower jaw, and also 

 by the inter-vertebral matter which holds the bodies of the ver- 

 tebrse together. And the third is represented by the trochleas 

 and sheaths, formed on the surface of bones for the gliding of 

 tendons. 



The principal constituent of this system is a strong fibrous 

 matter, which is intermixed with the cartilage, and has in some 

 places its surface covered by the latter. The fibres even by 

 superficial observation may be traced in various directions: in 

 some places they are parallel; in others intermixed and crossed 

 very much ; in others concentric. Their strength is of the first 

 degree. The cartilaginous part fills up the intervals between 

 the fibres, and gives to the whole structure its whiteness and 

 elasticity. 



The Fibro-cartilages may be converted by the action of hot 

 water into gelatine, but the process is slower than in the sim- 

 ple cartilage. The membranous, or first variety, differs how- 

 ever from the other two in this respect; for if it can be reduced 

 at all into gelatine, the quantity it yields is not perceptible. 



This system is destitute of perichondrium, with the excep- 

 tion of the first variety, in which it is distinguishable; but the 

 others either adhere to the bone, or are covered by a synovial 



