GROWTH OF THE CEREBRAL CORTEX 203 
TABLE 8—Continued 
SAGITTAL SECTION FRONTAL SECTION 
AVER- Area of cortex Total area Area of cortex 
SERIES, LITTER AND AGE |_ Ramrekt es 
GROUP BRAIN 
WEIGHT Area Area 
Cor- | Stand- Cor- | Stand-| Cor- | Stand- 
rected | ard | yigx-| rected | ard | rected) ard | pick. 
ness ness 
grams mm.2 mm.2 mm. mm.2 mm.2 mm.2 mm.* mm. 
Series IT 
F a, b OF832) 2078 19E4 |) 32") 38-0) |) Sb25) 186) | 729 9.9 
c-l 1.204) 26.0 | 25.9 | 14.4 | 47.3 | 46.7 | 23.4 | 22.3 | 10.9 
Series IIT 
G a-g OFS44) 20S S9SS 30) 3815 (S6E9 192) San OrZ 
h-j 15425 Gale Zon vero 46).2 le4onoe | e22n9) ees ml Ong, 
Average } (ks ID) Oe ast SG || aA) || WO BPA eyAa Tl | Ale ees|) a6 9.7 
(Sere l=] ERD) | WOT 24s an 246 MAT 45 10) | 4252 2256" 20 on LOR, 
Average | (C. I) 0.700| 15.7 | 16.5 | 12.3 | 31.9 | 32.7 | 15.2'| 15.2 | 986 
(Ser. I) J (Cy 1) 12226826215 (E261 eld. ON) 45.08 4722 | 2220N eo nce mise 
higher on the average by 3 per cent (1 to 4 per cent in individual 
cases) than the standard or controls. These results fit with the 
observation that in the underfed the cortical thickness in the 
frontal section is 8.7 per cent greater than for the standard 
(chapter 7). 
9. COMPUTED VOLUME OF THE CORTEX 
In a former paper (Sugita, ’18 b), it was assumed that, as the 
form of the cerebrum of the albino rat is relatively simple and 
nearly constant, the relative volumes occupied by the cortical 
cells could be computed, and compared among themselves, by 
reducing the data obtained by measurement to a simple geo- 
metrical form, since the cortical areas in the sagittal and frontal 
sections stand in fixed relations to the respective diameters 
L.F and W.D and to the cortical thickness of the sections from 
the same brain. These relations have been expressed as follows 
(Sugita, 718 b): 
