CONNECTIVE TISSUE 



43 



bedded. This substance is either secreted by the protoplasm of the cells, 



or it is produced by the metamorphosis of the outer protoplasmic layers. 



However much developed the intercellular substance is, according 



to recent research it is probably nearly always penetrated by very fine 





FIG. 38. Fatty tissue, after Ranvier (from Claus's 

 Ti'.i't-book of Zoology). F, Fat-cells ; B, connective tissue 

 fibrils. 



' \ 



FIG. 39. Chorda tissue, after Leydig. 



processes of the connective tissue cells, which are thus maintained in 

 organic union. Various hollow spaces are also frequently found in it. 



Cellular vesicular connective tissue arises from the vesicular con- 

 nective tissue above described by the cells secreting an external mem- 

 brane or cuticle which connects 

 them together, e.g. Chorda 

 dorsalis (Fig. 39). 



There are kinds of cellular 

 connective tissue in which the 

 cells do not take the vesicular 

 form, but remain compact and 

 mostly round. The inter- 

 cellular substance is incon- 

 siderable in comparison with 

 the cells. If it increases in 

 mass, the tissue passes into the 

 next form. 



In fibrous connective tis- 

 sue the intercellular substance 

 is considerable. When boiled 

 it yields glue. It is differen- 

 tiated into fibres, which often 

 unite in bundles, showing 

 the most varied arrangements. 

 They often run parallel, often cross each other, or branch and anasto- 

 mose with each other. The cells of the connective tissue seldom 



FIG. 40. Reticular connective tissue, after 

 Gegenbauer. 



