SYMPATHETIC CELLS: NORWAY RAT Soil 
2. Pigmented cells. In the standards the pigmented cells do 
not occur before puberty (table 5, Ping, ’21); the same is true 
for the Norways (table 6). In the standards there were found 
about 3.4 pigmented cells in each of the eleven ganglia in 
which such cells occurred, while in the Norways there were 
3.8 pigmented cells per ganglion, after these cells were first noted 
at 120 grams of body weight. 
However, in one ganglion of the Norways eighty-five, and in 
another thirty-seven pigmented cells were found, and it is these 
two cases which make the average for the Norways slightly 
above that for the standards. This is a surprising result, for, 
according to conmon teaching, we should have expected a 
much greater number of pigmented cells in the Norways than 
in the standards. Until thoroughly domesticated Norways 
are available, these relations cannot be interpreted. 
3. Vacuolated cells. These vacuolated cells were not found 
in the standards, but do occur in the Norways after maturity. 
Their number is small (table 6). As the data stand, the vacuo- 
lated cells are characteristic for the mature wild Norways. 
C. The increase in the diameters of the cells from birth to maturity 
As between the standards and Norways, it is possible to make 
this comparison between birth and maturity; table 10 gives 
what has been found. 
As the ratios and percentages show, the cells and nuclei have 
increased a little more in diameter in the Norway than in the 
standards, but this difference appears to depend mainly on 
the small size of these cells at one day of age in the Norway. 
If we choose the values at about 19 grams of body weight for 
the initial data, it is possible to compare the changes in the 
diameters of these cells, not only in the standards and Norways, 
but also with those of the cells in the spinal ganglia and ventral 
horn of the spinal cord, as observed in the standard rats (Don- 
aldson and Nagasaka, 718). The relations appear in table 11. 
This table 11 may be used for two purposes. First, it shows 
that within the limits of body weight chosen the percentage 
