The Morpholügy of Fiinctional Activity in the Ganglion Cells etc. 495 
li: 2.17 and the coefficient of Variation is .111. The fonrth group with 
a rapidly shifting size of the nucleus would be expected to give a greater 
ränge. In Table VI, the Standard deviation for the nucleus-plasma coeffi- 
cients of the thii d group is zb 1.65 and of the seventh group zb 2.64 and 
their coefficients of Variation are . 146 and . 171. 
Technic of Curve Construction. — The volumes of the cell and 
nucleus and the corresponding nucleus-plasma relation are cxpressed gra- 
phically by curves (Text Figs. 2—5, erected upon the upper and lower 
base lines respectively). The volurne curve represents not only the 
absolute size of any stage, but its size relation to the resting cell. This 
was accomphshed by using the figures for the average resting or starting 
point ceU and its nucleus in each seriös (Tables IV, V and VI) as the 
necessary divisors for reduction, instead of an arbitrary figui'e. The 
resulting quotients are taken as the ordinates in one half centhnetres. 
As the only possible way to obtain averages as well as to bring the 
numerous figures within the scope of curve construction, the figures 
for the volumes of the individual ceUs in these tables are grouped 
arbitrarily, according as they fall within certain liniits. For Tables IV 
and V, the large cells, they are grouped within each successive 25,000 
cubic micra, starting with 50,000, and for Tables VI and VII, of 
small cells, within each 5,000, starting with 15,000 and 40,000 cubic 
micra respectively. The one half centimetre divisions of the abscissa 
correspond to this arbitrary amount of size increase. But actuaUy the 
average volumes fall at varying places within each interval, that is, 
the average of each successive increment is only a part of the total 
arbitrary division. By erecting the ordinates to coivespond to the point 
within each interval upon which the increase actually falls, which is 
easily estimated, a more exact representation is obtained. The curve 
of ceU volurne becomes a straight line, thus graphically indicating the 
uniform and progressive increase to which the individual figures testify 
in the tables, and affording a better basis of comparison for the nu- 
clear variations. 
The corresponding nucleus-plasma curves are constructed by taking 
the base line as the level of the normal relation and constructing the 
ordinates according as the coefficient figures obtained from the average 
volumes differ from that of the resting cell, each unit being given the 
value of one millimetre. 
In Text Figure 5, the curve from the Pmkinje cell of man is re- 
produced. The divisions of the abscissa represent successive stages of 
activity and the procedure of construction is the same. 
