THE CONNECTIVE TISSUES. 



77 



a mere cement uniting the fibres within the bundles and lamina. 

 The flat or endothelial cells of the tissue lie within these bundles or 

 arc applied to their surfaces, forming a more or less perfect lining 

 to the lymph-spaces within the tissue and becoming continuous with 

 the endothelial walls of the lymphatic vessels. It is within these 

 spaces that the lymph accumulates after its passage through the 

 walls of the smaller bloodvessels, to find its way into the lymphatic 

 circulation. The spindle-shaped and cuboidal cells of the tissue lie 

 between or within the bundles of fibres embedded in the cement- 

 substance (Figs. 63 and 64). 



FIG. 63. 



\ 



Areolar tissue. Preparation from the subcutaneous tissue of a young rabbit. (Schiifer.) 

 c', endothelioid cell; p,p, cells with granular cytoplasm ; c, c, f, cells of the fusiform or 

 stellate variety not yet fully developed. The white fibres are in bundles pursuing a wavy 

 course ; the elastic fibres are delicate and form a very open network ; g, leucocyte of a 

 coarsely granular variety. 



Areolar tissue varies greatly in different situations in the density 

 of its structure i. e., in the size of the fibrous bundles and their 

 relative abundance, as compared with the number and size of the 

 spaces separating them. The name is derived from that form in 

 which the structure is open and the courses of the fibrous bundles 

 very diverse, so that they interlace, leaving relatively large spaces 

 between them. In this form it occurs in the subcutaneous tissues, 

 between the muscles, forming the loose fascia? in that situation, and 

 in many other parts of the body where adjacent structures are 

 looselv connected with each other. The sinuous course of the in- 



