9 
398 Some Racial Peculiarities of the Negro Brain 
The sexual differences are slight. The cross section area is larger in the 
male than in the female Caucasian, but the splenium of the female is rela- 
tively larger than that of the male, the isthmus likewise, while the body 
is relatively smaller in the female, and the genu is relatively about the 
same size. (cf. Table VIII? et seq.) 
Negro male types.—There are four types of the cross section outlines 
of the corpus callosum in the Negro male. 
Type I is a composite of eighteen cases. This type is representative 
and characteristic of the Negro race. The cross section of the corpus 
callosum is small. The splenium is large and club shaped, the remainder 
of the corpus callosum is small, narrow, long, and slender. The brain 
weight is from 1000 to 1200 grams. The brains are short, with narrow 
frontal lobes, and wide, bulging parietal region. The mesial outline is 
oval. The bodies from which the brains are removed are well nourished 
and muscular. The average height is 162 cm. (5 feet 4 inches), and the 
average weight is 67 kilo (148 pounds). ‘The age limit is 20 to 40 years. 
This represents a familiar type of Negro, the low, heavy set, muscular, 
dark-skinned young Negro, with small head, having the parietal bosses 
prominent and the frontal region low, narrow and receding. This is the 
lowest order and most prevalent type of Negro. There is evidence of 
little foreign blood. This type represents the Guinea Coast Negro, from 
which the subjects are probably derived. A few may be representative 
of the Hottentot Negro type. . 
Type IIL is a composite of eight cases. The cross section of the corpus 
callosum is larger than Type I and the anterior end is better developed. 
The splenium is also large. This may be considered as a sub-type of the 
one above, with evidence of more mixture with a foreign element. The 
brains are larger, weighing from 1100 to 1300 grams. The characteris- 
tics of the type are otherwise similar to those of Type I. 
Type III is a composite of ten cases. The cross section of the corpus 
callosum is long and large. The splenium is large and club-shaped; the 
genu is large and round; the isthmus and body are long and narrow. The 
brains are long (dolichocephalic), high, and narrow in front, wide and 
bulging in the parietal region. The weight is from 1200 to 1400 grams. 
The bodies are in a fairly well nourished condition, death being rapid or 
sudden (accident, pneumonia, heart disease, etc.) The height averages 
162 cm. (5 feet 4 inches), and the weight averages 63 kilo. (140 pounds). 
The men of this type are lighter skinned than those of Type I, and are 
built on broad lines in general. These are long armed, flat-footed, and 
loose-jointed individuals, not so compactly built or well knit as those of 
the previous types, and having long heads and faces, with high foreheads. 
