76 



J. N. Langlej r , On the Secretory Cells. 



ment with osmic acid, than they take on similar treatment after a 

 period of rest. Formerly I referred this to the whole of the non- 

 granular part of the cell, in which I did not then distinguish a net- 

 work and hyaline substance. The change of staining power shown by 

 the cells during secretion is however, I think, due to a change in the 

 hyaline substance, and not to a change in the network. It is chiefly 

 caused by the increased amount of hyaline substance. I say chiefly, 

 since it may be partly due to the fluid, which permeates the cell, 

 containing during secretion a greater proportion of substance capable 

 of reducing osmic acid than it contains during rest. 



The question now naturally occurs, What is the nature of the 

 hyaline interfibrillar substance? We have seen that as the granules 

 diminish, the hyaline substance increases, and that as the granules 

 increase, the hyaline substance diminishes; so that an obvious hypo- 

 thesis is that the protoplasmic network forms the hyaline substance 

 and then out of this manufactures the granules, which are, as we 

 know, converted during secretion into some one or more of the orga- 

 nic bodies of the fluid secreted. It is somewhat in favour of this 

 hypothesis, that in peptic glands there are apparently certain inter- 

 mediate stages in the formation of pepsinogen ; it may further be 

 noted that in the liver-cells, the hyaline substance is often indistin- 

 guishably mixed with a substance allied to glycogen. 



On the above hypothesis it would I think be most natural to re- 

 gard the network, and peripheral layer of the cell, as the only living 

 portions, but we have not as yet sufficient facts to allow us to come 

 to any definite conclusion, it may be that the hyaline interfibrillar 

 substance is protoplasmic (living) like the network, but is less diffe- 

 rentiated. The network appears to be the result of the two -fold ten- 

 dency of the protoplasm to form nbrillae and to store up substances 

 within its grasp; in most cases it is obviously not constant in form, 

 but is continuously altering the arrangement of its bars and the size 

 of its meshes. This is especially distinct in mucous cells in which 

 during secretion numerous fresh connecting fibrillae are formed. 



