GROWTH OF THE CEREBRAL CORTEX 197 
when compared with the standard values for the brains weighing 
the same. The cortical thickness at each locality of the controls 
was on the average fairly in accord with the standard (the detailed 
evidence for these conclusions is contained in table 6 a, not here 
published). 
In table 6 b (unpublished), in which the cortical thickness at 
localities VI, VII, and VIII of the frontal section was given, it 
was also clearly seen that the localities VI and VII are much 
greater in the cortical thickness, compared with those of the 
controls or the standard values of the same brain weight. The 
excess amounts on the average to more than 10 per cent. The 
locality VIII, at which the cortex is heterogeneous in laminar 
structure, did not show any significant difference in the cortical 
thickness, compared with the normal, though in some cases here 
and there it was found somewhat thicker in the underfed (the evi- 
dence for these determinations is contained in table 6 b, not here 
published). 
One more notable thing found in the cerebral cortex of the 
underfed was that, while in the controls and standards the 
locality VII is always somewhat greater in thickness than the 
locality VI, the relation has, in many cases (18 out of 44) of the 
underfed, proved to be reversed (A a, h; Bi; C a, ec; D d, e; 
Pew tks, ect hy G,a,.¢;-2,e andvh)), 
Generally considered, the localities which are situated nearer 
to the ventricular wall, the locus of the cell division, seem to have 
gained much more in the cortical thickness in the case of the 
underfed, while the localities remote from the matrix (for ex- 
ample, locality V) or the part constructed heterogeneously (for 
example, locality VIII) appear to be modified but little by under- 
feeding. 
As is to be seen in table 6, the average thickness of the cortex 
is in favor of the underfed Albinos. If compared with the stand- 
ard values for the same brain weight, the average cortical thick- 
ness in the underfed young (table 6) is greater than the standard 
on the average by 7 per cent (average of all eight litters, T. groups 
only), while the controls are greater on the average by only 1.8 
per cent (average of Litters A to E; C. groups only). According 
