210 C. W. M. POYNTER AND J. J. KEEGAN 
The sulci and gyri of the Negro brain are undoubtedly less 
complex and easier of interpretation than those of the Caucasian. 
But if, similar to brain weight, the complexity of fissuration is 
roughly indicative of intellect, it permits of only a very general 
comparison. 
CONCLUSIONS 
It is fully appreciated that conclusions drawn from the study 
of a small series of brains may be criticised on the ground of 
insufficient data, but the following will serve at least as an 
expression of the principal impressions gained from the review of 
the literature and the examination of this series of Negro brains. 
There is an essential difference between the Negro and the 
Caucasian brain. This consists of a fairly constant variation 
of the Negro brain from an imaginary average type of fissuration 
obtained by a study of a large number of Caucasian brains. 
But the Negro type thus established lies within the limits of 
individual variation for the Caucasian, hence it is not possible 
- to establish a single morphological feature which can be claimed 
as absolutely characteristic. 
The relative characteristics of the Negro brain do not necessar- 
ily all denote inferiority or closer relation to the apes, but per- 
haps it is safe to say that the balance of evidence sustains the 
long held idea of the inferiority of the Negro. 
This inferiority is expressed mainly in the frontal lobe by a 
flattened anterior association center representing actual de- 
ficiency of growth. This growth deficiency is farther evidenced 
by rostration, by the narrow gyrus frontalis medius and poorly 
developed sulcus frontalis medius, by the wide gyrus frontalis 
superior and by the irregularity of the fissures in the gyrus 
frontalis inferior. General features supposed to have a like 
significance are low average brain | ele and generally greater 
simplicity of fissuration. 
In the posterior association area activity of the growth process 
is expressed by a prominence of this region, by an operculation 
over the adjoining cortex and by the presence of a very prominent 
accessory sulcus in the region. 
