GROWTH OF THE CEREBRAL CORTEX 
TABLE 2 
185 
Showing for each test individual in Series II and III (Litters F, G, and H) the 
sex, age, and body and brain weights, at time of examination 
ety Gs SEX AGE OF KILLING BODY WEIGHT BRAIN WEIGHT 
days grams « grams 
Fa m 11 8.5 0.709 
b f 14 9.8 *0.954 
¢e f 17 13eo 1.106 
d f 19 Bo3} 1.218 
e m 20 12.4 1.148 
f m 23 ieS2 1.230 
g it 23 142 1.224 
h m 24 1133.5) 70 
1 f 26 17.0 1.197 
j f 30 24.2 1.219 
k m 30 18.7 1222. 
] f 40 40.0 1.310 
Ga m 8 Kok 0.679 
b f 8 7.4 0.703 
c f 10 10.3 0.864 
d m 11 9.8 0.929 
e f 12 8.8 0.907 
f m 15 oe 0.881 
g m 16 0.3) 0.948 
h m 18 9.6 1.119 
1 f 22 22 1.110 
j m 25 Wise 1.234 
Ha f 13 8.8 0.880 
b f il) 10.8 1.024 
c f 23 14.7 Ihe WSS} 
d f 28 peo 1.166 
e m 32 20.0 1.215 
f ii 37 19.3 OH 
g m 43 Pala il 1.295 
’ 
values having been calculated for each individual by the use of 
formulas given in ‘The Rat’ (Donaldson, ’15). 
length was chosen as the basis for comparison, because the in- 
crease in body length has proved less variable than body weight. 
Table 3 was condensed from the original complete table (table 
3a) by dividing the individuals, the tests, and controls within 
each litter into two groups, according to the observed brain 
Here the body 
