SECT. 26.] CONNECTIVE TISSUE. 53 



a. The elastic ligaments, in which the tissue, with but a slight 

 intermixture of connective tissue, and almost without vessels and 

 nerves, occurs, so to speak, pure. To this division belong the 

 ligamenta sub/lava of the vertebrae, the lig. nucha, certain liga- 

 ments of the larynx, the stylo-hyoid ligament, and the suspensory 

 ligament of the penis. 



6. The elastic membranes, which either appear as fibrous net- 

 works, or as fenestrated membranes, and occur in the coats of the 

 vessels, particularly in those of the arteries, in the trachea and 

 bronchi, and in the fascia super/icialis. 



Literature. — A. Eulenberg, Be Tela elastica, Berol. 1836. See also the 

 Treatises cited in § 24. 



§ 26. Connective or Areolar Tissue. — The elementary parts found 

 in connective tissue may be divided into such as are essential and 

 never-failing, and such as are more accidental, or occurring only 

 in certain places. To the former belong the proper connective or 

 areolar tissue, with its sometimes more homogeneous, sometimes 

 fibrous substance, as also the more homogeneous connective tissue; 

 to the others are to be reckoned the cells of connective substance 

 occurring, it is true, almost everywhere, in different forms, as plasm- 

 cells, cartilage-cells, or elastic fibres, also the fat-cells and certain 

 other cells without any well-defined character. Besides, many con- 

 nective tissues also contain a not inconsiderable quantity of an in- 

 terstitial substance. The proper connective tissue usually appears as 

 fibrous, and breaks up, more or less distinctly, into small divisions 

 — the bundles, — each of which, again, consists of a number of very 

 fine fibrils. The fibrils are distinguished from the finest elastic 

 fibres and muscular fibrils, which, in other respects, resemble them 

 most, by their small diameter (0-0003'" to 0-0005'"), their pale 

 colour, their homogeneous appearance, and the entire absence of 

 striation. They are held together by means of a small quantity 

 of a clear uniting matter, and thus form the bundles, as they are 

 called, which resemble, in many respects, those of the transversely 

 striped muscles, yet differ from them by the absence of a special 

 envelope, such as the sarcolemma, and by their smaller average 

 diameter (o'oo^" to 0-005'"). They are either long, slightly 

 undulating cords, of equal thickness throughout, which are not 

 connected with each other directly, but, being arranged in various 

 ways, parallel to and over each other, form large secondary and 

 tertiary bundles and lamella?: or thev coalesce to form a mesh- 

 work simdar to an elastic network, and constitute what I have called 



