SPECIES IDENTITY OF NUCLEUS-PLASMA NORM 481 



place in a cell qualitatively deteriorated in its power of recuper- 

 ation after the cycles of activity of a lifetime, whether naturally 

 or prematurely induced, now comes up for discussion. Suffi- 

 cient has been said to make the above distinction clear — even 

 if the quality of the cell has changed, every immediate reaction 

 must be a quantitative reaction founded on the coincident 

 quality of its resting cell or else the fundamental constitution 

 that makes it a nerve cell has changed. How this change in 

 quality brings about an actual and measurable change in the 

 nucleus-plasma relation may readily be shown. The qualitative 

 deterioration of age harmonically complements in every way the 

 quantitative exhaustion of a single cycle of excessive cell work. 

 In such an immediate exhaustion, the nucleus comes to exhaustion 

 first, and the process of activity ends with the balance of capacity 

 on the side of the plasma ('10). In terms of the nucleus-plasma 

 relation, the relation is upset in favor of the plasma. This is 

 proved by the excessive size of the plasma as stated in terms of 

 numerical coefficients, by the dechromatinization of the nucleus 

 and finally by the marked lagging behind of the nucleus in the 

 process of recovery (Dolley '11 a; Hodge '92). Old age is char- 

 acterized by an identical result in that the nucleus suffers re- 

 latively more. The first observable indication of senility is a 

 progressive irregularity of the nucleus, the 'final fatigue' of 

 Hodge. Next the karyosome goes. The shrinkage continues, 

 the nucleolar substance diminishes, and finally the nucleus 

 disappears, but nevertheless a distinct amount of plasmatic 

 substance remains before complete necrobiosis. In other words, 

 after each cycle of activity the cell comes back to a different level 

 of inferior capacity, the plasma always maintaining the end 

 advantage just as in a single overstrain. In senility, therefore, 

 there is just the same upset of the nucleus-plasma relation in 

 favor of the plasma, which becomes more pronounced at each 

 organic loss of substance and which finally becomes absolute, — 

 there is no longer a trace of nucleus. A priori, therefore again, 

 one could most confidently predict that the measured numerical 

 coefficient of this relation would be a higher figure. There has 

 not merely been a loss of recuperable substances, of which chro- 



THE JOURNAL OP COMPARATIVE NEUROLOGV, VOL. 24, NO. 5 



