159 



On the Relation 0/ Assimilation and Secketion to the 

 Functions o/Organic Life. By J. Gedge, M.B. Cantab., 

 M.R.C.S. 



Physiology suffers much from the want of definite nomen- 

 chiture. Organic processes specifically identical appear 

 generically distinct, in consequence of the separate terms used 

 in their description. 



It is on this account that I would inquire into what is 

 meant by secretion and assimilation, with a view to show that, 

 if our modern notions of physiology are correct, these processes 

 can no longer be described as though they had nothing in 

 common Avith the ordinary functions of organic life. 



Secretion as performed by the gland — the station where this 

 function is somewhat isolated — will be first considered. Cells 

 are the acknowledged agents in this process, as shown by the 

 indiscriminate use of the terms " secreting-cell " and " gland 

 cell," and as these histological units when they have arrived 

 at maturity all share alike — all perform a similar office — we 

 may limit our consideration of the function of the gland to that 

 of a cell. 



The old notion of cells was that they were vesicles of vary- 

 ing size, having various contents. But now it is allowed, 

 even by those who will go no further, that the vesicle must, 

 during at least part of its existence, be furnished with a nucleus 

 Avhich has definite chemical and physical characters. In this 

 country, as is well known, we are no longer fettered by the 

 vesicular notion of the histological unit: no longer imprisoned 

 by the constant presence of a cell-wall. That the cell should 

 have been universally considered to be vesicular in the early 

 days of histology is not remarkable, when we consider the 

 comparative ease Avith which such peculiar cells can be de- 

 monstrated : the imperfection of the optical instruments then 

 in use not enabling them to study carefully any but the large 

 histological units met with in the vegetable kingdom. Further- 

 more, it cannot be regarded as surprising that the cell first 

 described should have been considered the type, and that the 

 attempt should have been made to reduce all other cells to the 

 same formula. Besides, in animal cells where no cell-wall 

 existed, an apparent one could often be made by the action of 

 chemical reagents. Toy-cells have been constructed by 

 Mr. Rainey and others, having the conventional vesicular 

 character with the indefinite cell- contents simply by mingling 

 certain chemical compounds. 



The cell-wall then niu^t be understood to be simply a com- 



