TISSUES OF THE BODY. 



187 



6 and 7. Gelatinous and Reticular Connective-Substance. 

 113. 



Under the name of gelatinous or mucoid tissue and reticular connec- 

 tive-substance combined, we shall now consider a second series of tissues, 

 liable to great variation, and belonging to the group of connective-sub- 

 stances. This classification, however, can only be said to have a provi- 

 sional value : it remains for more accurate histogenic investigation to 

 show, at some future time, whether the mode of development of the 

 different tissues placed together here justifies or modifies our method of 

 arrangement. 



Gelatinous and reticular connective-substance appear at the first glance 

 separated by a wide gap from car- 

 tilage. Whilst in the latter we 

 have to deal with a tissue made 

 up of round cells held together 

 by a solid glutinous intermediate 

 matter, the plan of the tissues 

 with which we are now engaged 

 is completely different. They are 



all of them more Or less Soft, partly T\K. 176. Gelatinous tissue with roundish cells 



swollen up into a glutinous condi- from the vitreous humour of a human foetal eye - 

 tion, or in other rarer cases even present themselves in the liquid form. 



Only in exceptional cases do their cells preserve their spherical form : they 

 present themselves, as a rule, in most character- 

 istic figures, radiated and stellate, and united with 

 each other by means of simple or branched pro- 

 cesses, forming networks of cells (figs. 177 and 

 178). 



The system of meshes so formed varies as to 

 its contents very considerably, apart from the 

 differences in the size of its meshes. 



In a certain number of the tissues which 

 may be reckoned in this category, the net' 

 work formed by these elements is occupied by a 

 structureless, watery jelly, containing mucin or 

 some allied substance, when we term it a gelatinous 

 or mucoid tissue (fig. 177). 



A second and more extensive group shows 

 us these interstices, instead of being occupied 

 by a mucoid mass, filled rather with innumerable 

 granular cells, which correspond exactly with 

 the elements of lymph. We have thus pre- 

 sented to us the most widely distributed species 

 of reticular connective-substance (fig. 178). It 

 has been named " cytogenous connective-sub- 

 stance " by Kolliker, and by His " adenoid sub- 

 stance." 



Another series of connective matters belonging 

 also to this group in our opinion, encloses, in a Fig. 177. Gelatinous tissue with 



,, A , , iii- 11 i i stellate cells, from tlie enamel- 



USUally narrow-meshed and delicate cellular net- organ of tie human embryo. 



work, another kind of contents, e.g. chiefly, ner- 

 vous elements (fig. 179), or also, though much more rarely, masses of 



a, 



