J. Bretland Farmer. 
n9 
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Botaniste sev. 5, 1896. 
“NUCLEAR OSMOSIS” 
And its Assumed Relation to Nuclear Division, 
By J. Bretland Farmer, F.R.S. 
mHE attempts which have been made within the last thirty 
years or so to unravel the secrets of the processes accom¬ 
panying a nuclear division, group themselves rather naturally into 
two classes. The one, prior in time and more naive in character, 
seeks to explain the complex series of changes as the outcome of 
the operation of correspondingly complex cell-structures. The 
second and more modern efforts have been in the direction of 
shewing that the changing configuration of a dividing cell is the 
expression of the series of chemical reactions which are conditioned 
and limited by the ultimate physical structure of the protoplasm 
in which they occur. Unfortunately our knowledge both of the 
reactions and of the conditions is extremely fragmentary as yet, 
but it is only by pushing outposts into unexplored ground that new 
discoveries can be made. It is something to have arrived at a 
conviction that not in reliance on a Dens ex machina does the 
possible extension of knowledge lie, but rather in investigations 
on the origin and meaning of the structures themselves. 
Of course progress has been slow, but this is the inevitable 
consequence of attacking problems of so high an order of difficulty. 
Many mistakes have been made in the past, and many will be made 
in the future. There is divergence of opinion on matters which 
