78 
No doubt, this is a very striking difference, but it loses 
much of its apparent systematic value, when viewed by the 
light of certain other equally indubitable facts respecting 
cranial capacities. 
The first of these is, that the difference in the volume of 
the cranial cavity of different races of mankind is far greater, 
absolutely, than that between the lowest Man and the highest 
Ape, while, relatively, it is about the same. For the largest 
human skull measured by Morton, contained 114 cubic inches, 
that is to say, had very nearly double the capacity of the 
smallest; while its absolute preponderance, of 52 cubic 
inches—is far greater than that by which the lowest adult 
male human cranium surpasses the largest of the Gorillas 
(62 —341=— 271). Secondly, the adult crania of Gorillas 
which have as yet been measured differ among themselves by 
nearly one-third, the maximum capacity being 34.5 cubic 
inches, the minimum 24 cubic inches; and, thirdly, after 
making all due allowance for difference of size, the cranial 
capacities of some of the lower apes fall nearly as much, 
relatively, below those of the higher Apes as the latter fall 
below Man. 
Thus, even in the important matter of cranial capacity, 
Men differ more widely from one another than they do from 
the Apes; while the lowest Apes differ as much, in propor- 
tion, from the highest, as the latter does from Man. The last 
proposition is still better illustrated by the study of the 
modifications which other parts of the cranium undergo in 
the Simian series. 
It is the large proportional size of the facial bones and the 
great projection of the jaws which confers upon the Gorilla’s 
skull its small facial angle and brutal character. 
person (1783 grammes). The lightest adult brain recorded (720 grammes) was 
that of an idiotic female. The brains of five children, four years old, weighed 
between 1275 and 992 grammes. So that it may be safely said, that an average 
European child of four years old has a brain twice as large as that of an adult 
Gorilla. 
