5° 



ELASTIC TISSUE. 



[sect. 25. 



The recognition of the true structure of the cartilage-cells is of quite recent 

 date, and first became possible when observers began to scrutinise more 

 closely the relation of the cellular elements to each other in connective tissue, 

 cartilage, and bone. It was first demonstrated by Virchow, that the cartilage- 

 corpuscles of authors, or the contents of the cartilage-lacunae, are really deli- 

 cate-walled cells, and not merely cell-contents, as had been generally assumed. 

 Now, since it had been previously shown by myself and others, in opposition 

 to Reichert and Bcrgmunn, that the cartilage lacunse possess distinct walls, 

 and are separable cellular structures, it was but natural to apply the doctrine 

 of the primordial utricle, and of the external secondary cell-membranes, to 

 cartilage-cells, as was accordingly done by Remult and myself (see antea). 

 The primordial utricle of the cartilage-cells is most readily observable in 

 reticular cartilages ; and, owing to their peculiar matrix, these are also best 

 adapted for convincing the most incredulous of the existence of cartilage 

 capsules as distinct structures different from the matrix, and belonging to the 

 cartilage-cells. In true cartilages, moreover, the cartilage-capsules can fre- 

 quently be very readily isolated, particularly, as Bonders long ago pointed out, 

 by boiling, and the proper cartilage-cell also recognised, the latter especially 

 in ossifying cartilages ( Virchow). 



Literature. — Meckauer, Be penitiori Cartilaginum Structurd Biss.,Vratis\., 

 1836. J. Muller, in Poggendorfs Annalen, 1836^.293. Eathke, in Fror. 

 Not., 1847, p. 306. A. Bergmann, Be Cartilaginibus Bisq. micr., Mitavise, 

 1850. Compare, further, the Treatises of Virchow and Remak, cited above, 

 under Connective Tissue ; also F. Hoppe, liber die Gewebelemente der Knorpel, 

 Knochen und Z'dhne, in Virchow's Arch., v. p. 170. 



§ 25. Elastic Tissue. — The elements of the elastic tissue are 



Fig. 17. 



darkly contoured, cylindrical or riband-like 

 fibres, varying in their diameter from immea- 

 surable fineness to 0-003'", or even o , oo5'" (in 

 animals even o - oo8") in thickness, and when 

 they lie together in masses, presenting a 

 yellowish colour. These elastic fibres, as they 

 are called, are, when fully formed, completely 

 solid, but may subsequently contain small ca- 

 vities at certain places, which in one animal, 

 the giraffe (Quekett, Histological Catalogue, 

 i.), appear so regular, that the fibres acquire a 

 Mca mX ITo^nimo- beautiful transversely striped appearance. The 

 borders of the elastic fibres are, as a rule, quite 

 even, but appear, in rarer cases, jagged, or, 

 as Virchow observed in newly-formed tissues, even beset with very 

 many longer and shorter pointed processes. Hitherto the nuclear 

 fibres have been separated from the elastic fibres. Since, however, 

 the former differ in nothing but their diameter from the latter ; 

 further, since all elastic fibres are originally just as fine as the 



tu 



nary artery of the horse, 

 with holes in the fibres ; 

 magnified 350 times. 



