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CHAPTER SECOND. 



ORGANS OP ATTACHMENT, OR LIGAMENTS. 



THE solid parts of the skeleton, whether external or in- 

 ternal, are held in connexion and are allowed to move on each 

 other with more or less freedom, by means of soft parts, 

 which are almost as inert in their vital properties as the 

 bones themselves, and this low degree of vitality better 

 enables them to sustain the stretching and compression to 

 which they are continually subjected. Even in the highest 

 animals the ligaments which connect the bones, and 

 the cartilages which bound their contiguous sufaces, are 

 scantily supplied with blood-vessels and nerves, and have a 

 corresponding low degree of sensibility, great slowness of 

 growth and reproduction, and great tenacity of life. In the 

 lowest tribes the component pieces of the skeleton are held 

 together by the simplest mode of union, they have not their 

 points of contact protected by a layer of soft cartilage, 

 lubricated with synovia, and connected by capsular ligaments 

 and external ligamentous bands, they are partially or entirely 

 imbedded in a common tough connecting matter, which, by 

 its elasticity, admits of the few required motions. No 

 articulations nor ligaments appear in the soft, gelatinous, 



