106 MAN AND THE LOWER ANIMALS n 



Sections of the skulls, however, show that some 

 of the apparent defects of the Gorilla's cranium 

 arise, in fact, not so much from deficiency of brain- 

 case as from excessive development of the parts of 

 the face. The cranial cavity is not ill-shaped, and 

 the forehead is not truly flattened or very retreat- 

 ing, its really well-formed curve being simply dis- 

 guised by the mass of bone which is built up 

 against it (Fig. 17). 



But the roofs of the orbits rise more obliquely 

 into the cranial cavity, thus diminishing the space 

 for the lower part of the anterior lobes of the 

 brain, and the absolute capacity of the cranium 

 is far less than that of Man. So far as I am 

 aware, no human cranium belonging to an adult 

 man has yet been observed with a less cubical 

 capacity than 62 cubic inches, the smallest 

 cranium observed in any race of men by Morton, 

 measuring 63 cubic inches ; while, on the other 

 hand, the most capacious Gorilla skull yet 

 measured has a content of not more than 34J 

 cubic inches. Let us assume, for simplicity's 

 sake, that the lowest Man's skull has twice the 

 capacity of that of the highest Gorilla. 1 



1 It has been affirmed that Hindoo crania sometimes contain 

 as little as 27 ounces of water, which would give a capacity 

 of about 46 cubic inches. The minimum capacity which I 

 have assumed above, however, is based upon the valuable tables 

 published by Professor R. Wagner in his Vorstitdien zu einer 

 wissenscliaftlichcn MorpJiologie und Physiologie des menschlicken 

 Gehrins. As the result of the careful weighing of more than 

 900 human brains, Professor Wagner states that one-half 



