VARIETIES OF CONNECTIVE TISSUE. 65 



As long as we consider a given object to belong to this kind 

 of connective tissue from its external appearance alone, and 

 without regard to its chemical and physiological characters, it 

 is difficult to meet the objection that our generalisation is 

 founded on comparatively coarse analogies, which could no 

 longer be maintained were the tissues to be subjected to more 

 accurate chemical and physiological investigation. It may, on the 

 other hand, however, be remarked that a considerable quantity 

 of the connective tissue in the body at a particular stage of its 

 development presents the appearance of gelatinous tissue, and 

 also that in pathological neoplastic formations proceeding from 

 connective tissue the same condition is frequently met with. 



b. A very delicate retiform connective tissue, fulfilling the 

 purposes of support and protection, and therefore here first men- 

 tioned amongst those possessing similar characters, occurs in the 

 connective tissue of the eye and in the interior of the nervous 

 centres (Neuroglia, Virchow). That this is really a form of 

 connective tissue was first maintained by Max Schultze,* 

 with whom Kolliker,-J- Virchow,J Deiters, and others are in 

 accordance. In regard to the particular features presented by 

 this form, we must refer to the special descriptions of the 

 several organs. Hirzel and Frey|| consider they have met the 

 same tissue in the hybernating glands of some mammals. 



c. A remarkable form of connective tissue occurs in the sup- 

 porting and investing reticulum of the glands of the lymphatic 

 system and allied organs in connection with their blood capil- 

 laries, and around the fasciculi of fibrillar connective tissue. 



In the lymph glands and analogous structures such as the 

 glands of Peyer, the solitary glands of the intestine, the 

 mucous membrane itself of the alimentary canal, the tonsils, 

 the follicles at the root of the tongue, the trachoma glands of the 



* De Retince Structura Penitiori, Bonn, 1859. Archiv fur Mikroskop. 

 Anatomie, Band ii., p. 261. 



f Geicebelelire. Leipzig, 1867, p. 266. 



\ Die Krankhaften Geschwulste, Band ii., p. 128. 



Untersuchungen ilber Gehirn und Riickenmark lierausgegeben von Max 

 Schultze. Braunschweig, 1865, p. 27. 



II Frey, Histologie und Histochemie, Leipzig, 1867, p. 233 ; und Zeitschrift 

 fur wissenschaftliche Zoologie, Band xii., p. 165. 



