SYMPATHETIC CELLS: ALBINO RAT 287 
On examining the ratios between the values at one day and at 
365 days, as shown in columns D and E of table 1, it is found that 
the cells in the male have increased in diameter 1.55 times, and 
in the female 1.58 times, while the nuclei in the male have increased 
1.17 times and in the female 1.32 times. This shows that 
the difference between the male and female in the growth of the 
nuclei in the course of one year is greater than that in growth 
of the cells, but the cells in both sexes have a greater rate of 
growth than do the nuclei, as indicated in table 1. 
Diameters of CellS and Nuclei in micra 
1 a 
ar] 
0 20 50 100 200 300 350 
Chart 1. Based on table 1 and giving the computed diameters of the cells 
and their nuclei according to sex—on age in days. Males 
Females ------------ --- 
The graphs in chart 1 show that the increase in the diameter 
of the cell body is rapid for the first twenty-five days and then 
becomes slower. ‘There is a similar change in the nucleus, though 
the change in the rate of growth in this case is less marked. From 
25 to 365 days the diameters of the cells and of the nuclei of the 
two sexes have increased as shown in table 3. 
In column F of table 1 are given the ratios between the diameter 
of the cell body and that of the nucleus. Generally speaking, 
the cell has about twice the diameter of the nucleus throughout 
the series of measurements as given in table 1, but if we consider 
the ratios carefully, we see that there is an increase in the ratios 
