VII. 



CONNECTIVE TISSUE. 



DEFINITION AND DIVISION. 



THE term connective tissue is applied to that tissue which con- 

 stitutes the frame of the body (skeleton), covers the articular 

 surfaces of bones (articular cartilage), incloses the whole body 

 (derma of skin), supports and surrounds muscles and nerves 

 (tendon, perimysium, perineurium), produces flat layers for all 

 epithelial formations (basement layers), contains as a physiologi- 

 cal product fat-globules (fat-tissue), and forms the blood and 

 lymph vessels. It is composed of living matter which, having a 

 reticular structure, contains in its meshes a lifeless, more or less 

 solid, interstitial basis-substance. At certain regular intervals the 

 reticulum is nodulated, and these nodules are the formerly so- 

 called connective-tissue cells, preferably termed connective-tissue 

 corpuscles. 



The distinguishing feature of connective tissue is the inter- 

 stitial basis-substance, which is generally termed " glue-yielding," 

 because some of its varieties on being boiled furnish gelatine, 

 although other varieties, by the same treatment, yield a substance 

 which is not strictly glue, but kindred to it. For twenty years 

 (1840-1860) a lively controversy was carried on regarding the 

 relation between the basis or intercellular substance and the 

 plastids, the connective-tissue cells. Henle was the main repre- 

 sentative of the view that the intercellular substance contains only 



