536 HENRY H. DONALDSON AND G. NAGASAKA 
of rats. The object of making the sections and measurements in 
different planes was to determine whether the long axes of the 
cells were in a fixed relation to the long axis of the cord. There 
is a slight difference between the long axes in these two cases in 
favor of the longitudinal section, but the difference is too small 
to warrant placing any emphasis on it at present. This problem . 
of orientation must be taken up later. 
TABLE 5 
Mean diameters in micra of the ten largest spinal cord cells, from the ventrolateral 
area of the ventral horn as they appear in a longitudinal section. Long diameter, 
short diameter, and ‘computed diameter,’ which is the square root of the product of 
the long and short diameters. Also the mean diameters of the respective nuclet. 
The ratio of the last to the first entry ts given at the foot of each column 
CELLS 
BODY WEIGHT SRE 
Long diameter Short diameter Computed RLS. 
grams 
18.7 B2ne 19.0 24.8 13.0 
25.2 33.6 18.2 24.8 1S2 
42.8 34.8 18.4 Aa) 3} 13.4 
58.9 35.8 18.8 25.9 14.2 
82.0 37.6 22.4 29.0 15.6 
114.5 40.0 Done 30.5 16.8 
117.0 36.0 22.4 28.4 14.8 
153.5 39.0 25.2 31.4 16.4 
180.8 37.4 22.8 29.2 15.0 
228 .8 36.6 23.6 29.4 ivan 
236.5 38.8 22.8 29.8 16.8 
314.1 37.0 22.8 29.2 15s 2 
Rahlosiece-cece 1:1.2— ihe2 Weber 1:1.2-— 
In the meantime we shall treat the data as though the position 
of the long axis of the cells in relation to that of the cord was 
indeterminate, and, for discussion, the two series of data may be 
combined. Table 6 contains the combined values for the two 
series, taken from tables 4 and 5. 
In order to determine the relations of the values given in tables 
2 to 5 it has seemed best to condense these tables by taking 
the means of the entries, in successive groups of three, as thus 
several relations among the data can be brought out more clearly. 
