330 CHESTER A. STEWART 
SPINAL CORD 
The weight of the spinal cord (table 2) like the brain in my 
controls averages slightly higher than the Wistar norm for rats 
of corresponding length, the only exceptions being the two con- 
trol males and one control female weighing about 70 grams net. 
The differences are less marked when the body weight is used as 
a basis for comparison. As compared either with my controls 
or with the Wistar tables, the spinal cord is constantly heavier 
in the test rats. In the test rats at three and ten weeks of 
age, the average increase (sexes combined) amounts to approxi- 
mately 70 per cent, and at six weeks to about 38 per cent. In 
the other groups of test rats underfed for long periods, the in- 
crease while still considerable, is somewhat less marked, varying 
from 29 to 56 per cent in the various groups (table 2). 
Donaldson (’11) also found an increase in the weight of the 
spinal cord in rats held at 34 grams body weight from 30 to 51 
days of age. 
Jackson (15 b) found that during maintenance there was a 
well-marked increase in the weight of the spinal cord, amounting 
to 36 per cent in those at maintenance from three to ten weeks 
of age. 
It therefore appears that in young rats underfed at various ages 
the spinal cord shows a remarkable tendency to grow, this ten- 
dency being relatively strongest in those stunted from birth. 
This increase in weight is also maintained (to a lesser degree) 
in young rats underfed through long periods of time. 
According to Jackson (’15 a) the spinal cord suffers practically 
no loss in absolute weight during acute and chronic inanition in 
adult rats. 
EYEBALLS 
The weight of the eyeballs in my controls (table 2) averages 
constantly higher than the Wistar norm for rats of corresponding 
length. The differences, however, are not striking and are 
probably due largely to differences in body weight (my rats . 
averaging slightly heavier than the Wistar norm for correspond- 
ing length). 
