52 TEXT-BOOK OF PHYSIOLOGY. 



Elastic Tissue. The fibers of elastic tissue are usually associated 

 in varying proportions with the white fibrous tissue; but in some 

 structures as the ligamentum nuchae, the ligamenta subflava, the 

 middle coat of the larger blood-vessels the elastic fibers are almost 

 the only elements present, and give to these structures a distinctly 

 yellow appearance. The fibers throughout their course give off 

 many branches, which unite with adjoining branches to form a more 

 or less close network. As the name implies, these fibers are highly 

 elastic, and are capable of being extended as much as 60 perjcent. 

 before breaking. (See" Fig. 10.) ' 



Cartilaginous Tissue. This form of connective tissue differs 

 from the preceding varieties chiefly in its density. As a rule, it is 



FIG. 10. ELASTIC FIBERS. X 560. A. Fine elastic fibers, /, from intermuscular 

 connective tissue of man; 6, connective-tissue bundles swelled by treatment with 

 acetic acid. B. Very thick elastic fibers, /, from ligamentum nuchae of ox; b, 

 connective-tissue bundles. C. From a cross-section of the ligamentum nuchae of 

 ox; f, elastic fibers; &, connective-tissue bundles. 



firm in consistency, though somewhat elastic. It is opaque, bluish- 

 white in color, though in thin sections translucent. 'All cartilaginous 

 tissues consist of connective-tissue cells embedded in a solidgrouncl 

 * substance. According to the amount and texture ot the ground 

 substance, three principal varieties may be distinguished: 

 i . Hyaline cartilage, in which the cells, relatively few in number, are 

 embedded in an abundant quantity of ground substance (Fig. 1 1) . 

 The body of the cells is in many instances distinctly marked off 

 from the surrounding substance by concentric lines or fibers, 

 which form a capsule for the cell. Repeated division of the cell 

 substance takes place, until the whole capsule is completely 



