THE CELL DOCTRINE. Ill 



as in muscle and nerve. In some situations, it is 

 indeed lifeless, as when it becomes the secretion of 

 glands, as bile and milk, or the peripheral part of 

 epithelial cells. It simply is devoid of a power of 

 multiplying or growing by itself, depending for its 

 increase upon the conversion of the germinal matter. 

 Hence we have been inclined to suggest the term 

 "non-germinal, "or "non-germinating "matter, since 

 this is the only attribute common to all formed ma- 

 terial. 



In structure, formed material or non-germinal mat- 

 ter is varied. Thus, it is typically without structure 

 in the red blood disc; again it exhibits distinctive 

 structure in the striped sarcous matter of muscle, 

 and in the fibrous intercellular substance of white 

 fibrous tissue or fibro-cartilage. 



As formed material is produced on the periphery 

 of germinal matter, previously existing formed ma- 

 terial is pushed outward, so that the oldest formed 

 material is that most remote from the germinal mat- 

 ter, and the youngest lies immediately adjacent to it. 



Intercellular substance, whether of cartilage or white 

 fibrous tissue, is formed material, resulting from the 

 conversion of the germinal matter, which constitutes 

 the cartilage corpuscle on the one hand, or the con- 

 nective tissue corpuscle on the other. It is not of 

 the nature of a deposit from the bloodvessels which 

 subsequently becomes differentiated. Young carti- 

 lage cells, like all young cells, consist of almost pure 

 germinal matter, and the capsule of the cartilage 

 corpuscle is but formed material, more or less con- 

 tinuous and inseparable from the intercellular sub- 



