178 NAOKI SUGITA 
According to my previous studies on the normal development 
of the cerebral cortex during the period of most active growth 
(Sugita, “17, “17 a, 718 a, “18 .b; 718 ¢), 1t was found that the 
growth of the cortex is precocious and that its elementary organ- 
ization (that is, the cortical thickness, the cortical cell number 
and cell size, ete.) is nearly completed at the time of weaning, 
when the albino rat is twenty days of age. The investigations 
by the several authors cited above were, however, made mostly 
on animals which were already weaned, because, of course, feeding 
experiments necessitate a strict food control. But at this stage 
(after weaning), the elementary organization of the cerebral 
cortex is already completed. For my object, which was to 
determine the effect of starvation on the early development of the 
cerebral cortex, it was necessary to use animals in which the 
growth of the cerebral cortex was still in active progress and to 
note the influence upon the organization of the cortex of longer 
and shorter periods of inadequate feeding. 
For this it is necessary to use the very young animals, still de- 
pendent on the mother. During this period the growth impulse 
in the brain is especially strong and the results of underfeeding 
are somewhat peculiar, as the brain weight may even increase 
under severe underfeeding. In complete starvation, growth is 
stopped and the brain weight remains constant. Thus, von 
Bechterew (’95) studied on new-born kittens and puppies the 
influence of complete starvation upon the brain weight. His 
results were that the brain weight, at the time of death after three 
or four days of starvation, was like the initial weight of the organ 
at birth. The brain had not grown, but also it had not lost in 
weight. 
By applying severe starvation to the albino rat immediately 
after birth, it has been my object in the present study to obtain 
answers to the following questions: 
1. How far will the growth of the body and of the brain be 
arrested? 
2. Will the normal relation between body weight, body length, 
and tail length be modified? 
