318 DAVID H. DOLLEY 
ciation with volumes then a graphic representation of the nu- 
cleus-plasma relation. 
In order to get all three graphs of figure 2 on the same page 
the cell and nuclear figures were each further reduced one-fourth. 
The lower graph is the area, the middle the relative volume as 
a cylinder, the upper the relative volume as a parallelopiped. 
The solid lines are cell, the broken lines nuclear sizes in each 
case. As the relative sizes to each other by the three methods 
have no significance, the graphs are conveniently placed one 
above another, and their abscissas omitted for simplicity. 
The three nucleus-plasma curves from the exercised animal are 
made by plotting the coefficient figures for each set (table 3), 
reduced one-half, as ordinates above a base line. They are like- 
wise placed one above another in figure 3 for easy comparison, 
irrespective of their comparative heights, and their abscissas are 
omitted. The comparison is with the resting cell in each case 
and not in terms of absolute values. However, the interrupted 
scale to the left shows in centimeters the actual height for the 
one-half reduction of each curve. 
The technical methods may now be compared at a glance. 
The planimeter or area method affords results that are abso- 
lutely identical in every detail with the diameter method, both 
in size and in nucleus-plasma relation. Note the crossings of 
cell and nuclear lines in figure 2. Even the slight variation from 
the usual steady upward trend from stage 9 to stage 11 in the 
nucleus-plasma curve shows up in area and parallelopiped. Pre- 
vious results by the diameter method are merely confirmed, no 
more, no less. 
The planimeter or area method alone, therefore, has no spe- 
cial or superior value. ‘True, it gives the exact areas of any sec- 
tion through cell and nucleus. It is a valuable check on the diam- 
eter method, particularly in the case of irregular cells, but 
the irregularity makes consideration of their three dimensions 
essential. 
On the other hand, exclusive use thereof, in my opinion, would 
tend to make one think in terms of two dimensions, as Kocher 
did, for his only reference to a third dimension is found in the 
