384 Some Racial Peculiarities of the Negro Brain 
but there are other similar ones. Spitzka has measured the cross section 
“area of the corpus callosum in the brains of ten eminent men, and he 
finds the average area higher than in ordinary men. Their average brain 
weight was also greater than in ordinary men. The weight of Prof. 
Joseph Leidy’s brain was estimated to be 1545 grams or possibly more, 
and the corpus callosum measured 10.6 sq. cm. in sectional area. The 
symbol representing this brain may be found in Chart V and its unusual 
CAUCASIAN = O 
NEGRO ae 
MULATTO = © 
CHART V.—RKelation of the area of the cross section of the corpus callosum 
(ordinates) to brain weight (abscisse). The heavy black lines enclose the 
majority of the Negro symbols and exclude the majority of the Caucasian. 
position attracts immediate attention. This may be an exception to the 
rule that the cross section area of the corpus callosum varies directly 
with brain weight and at a proportionate rate, and exceptional size of 
the corpus callosum may mean exceptional intellectual activity. One of 
the Negro brains, however, had a corpus callosum with a cross section 
area of 9.1 square centimeters, which is nearly 2 square centimeters 
