Abstract
1) I devised a new method which demonstrates as a curve the proportion of volume of whole cell-bodies to that of all gray matter in the cerebral cortex.
2) Though the curve has no direct relation to forms and sizes of cell-body, the quantity of cell-volume at the voluntary zones horizontal to the cortical surface can be easily got at a glance.
3) Using this method, areas 4 and 17, where it may be visible the most specific cytoarchitectonic structure, were chosen to be examined. Following results were obtained:
i) At area 4, the volume-quantities at the superficial zones of the cerebral cortex were rather high and decreasing with depth, except a zone which corresponds with a place of Betz's cell, where a sharp peak was shown. The general transition of the curve did not correspond with the stratification which had been defined by cytoarchitectonic investigators.
ii) Contrary to area 4, at area 17, there was some correlation between the curve and the stratification. For instance, a curve has five peaks, which correspond with II, IVa, IVb, IVc, and Va by Brodmann. And the highest quantity was seen at II layer, the lowest at IVc, and at the other laminae they took intermediate values between them. These relations were almost the same for five cases.
The curves obtained at summit, side, and valley of a gyrus differed with each other.
4) Some technical problems and the possibility for measurements of the whole volume of cell-bodies in the cerebral cortex were discussed.
