YELLOW ELASTIC LIGAMENTOUS TISSUE. 



229 



ance and their texture a long time. The dead parts separate 

 from the Jiving in large portions, in a way which has a con- 

 siderable analogy with the exfoliation of bones. 



The tendons and their expansions, and the various fasciae, 

 have the same chemical composition. If boiled a long time, 

 they dissolve completely, and form the substance called by 

 chemists gelatine, or pure glue. 



The ligaments differ from them in some respects. When 

 boiled they yield a portion of gelatine, and do not dissolve 

 entirely ; but are said to retain their form and even their 

 strength, after a very long boiling. The composition of the 

 part so insoluble in water, has not yet been ascertained. 



Of the Yellow Elastic Ligamentous Tissue. 



Fig. 49.* — This is a modification of 



the common ligamentous tis- 

 sue, which though not usual- 

 ly treated apart, differs from 

 it in many essential particu- 

 lars. It contains, according 

 to the younger Girard, some 

 fibrine in its composition ; it 

 is eminently elastic, and is 

 placed to give resistance and 

 support to parts, where in 

 other animals, we meet with 

 muscular fibres, for which it is in some sort a substitute. In some 

 situations it is of a deep yellow color, and rarely presents the 

 silvery aspect of the common tissue. It forms the middle coat 

 of the arteries, the ligaments between the bridges of the verte- 

 brae, the ligamentum nuchae in quadrupeds with heavy pen- 

 dant heads, the elastic involucrum of the corpus cavernosum' 

 and spongiosum penis in the male, of the clitoris in the female, 



* Reticulate elastic tissue from the ligamenliim nuclice of the horse magnified 

 to 200 diameters (from Gerber). a. Loosened elastic tissue with the meshes 

 opened, b. Elastic tissue in its natural condition, the meshes close; the fibres 

 being disposed in lines and layers, parallel to one another. 



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