258 NAOKI SUGITA 
thickness and staining with methyleneblue. Hammarberg claims 
that after twenty-four hours in 95 per cent alcohol the brain 
piece shrinks about 20.5 per cent in volume and the cortical 
thickness diminishes by 0.1 to 0.2 mm., but that during the 
subsequent procedures no significant size changes occur. Ac- 
cording to his results, the gyri frontales have the thickest cortex 
(about 3.0 mm.) and the lobus centralis or insula is the thinnest 
among localities typical in cell lamination. This latter part as 
measured by Donaldson shows the thickest cortex. 
Campbell (’05) gave two series of determinations of the cortical 
lamination of the human brain, after cell staining and after fiber 
staining, represented by uniformly magnified illustrations of the 
sections at the several localities. Making use of his iltustrations, 
I obtained a series of cortical thicknesses at different localities 
(table 8), reduced to the actual thickness on the slide, by divid- 
ing the direct measurement on the illustration by the magnifi- 
cation. His sections were taken from the material fixed in 
Miiller’s or Orth’s fluid and imbedded in celloidin, cut at 25 
micra, and stained with thionine. The general average thick- 
ness thus obtained, the two series combined, is about 2.3 mm. 
Brodmann (’08) also has measured the thickness of the cortex 
on the human brains at forty-two different localities on sections 
prepared by two different methods: one set was fixed in 4 per 
cent formaldehyde, imbedded in paraffine, and stained by 
Nissl’s method for cell study, and the other, fixed in Miiller’s 
fluid, imbedded in celloidin, and stained by Weigert’s method 
for the myelin sheaths. His results, which are the averages 
from brains between seventeen and forty-five years in age, are 
also tabulated in table 8 for a comparison. The general average 
thickness given by Brodmann is about 3.09 mm. 
Kaes (’07) also studied the growth in thickness of the human 
cerebral cortex, measured at twelve different localities on the 
hemisphere, using sections fixed in Miiller’s fluid and stained by 
Weigert’s method. His results are remarkably high, giving 4.9 
mm. on the general average. His method of measuring the cor- 
tex is so arbitrary and peculiar, however, that his results are not 
included in this table 8. 
