332 



MENTAL FACULTIES. 



From this table it appears, that the smallest mean cranial capacity 

 is found in the Hottentots and Australians, which is 75 cubic inches; 

 whilst that of the Teutonic races is 92 cubic inches. It may be inte- 

 resting to add, that from the examination of four skulls of the Enge-ena, 

 a quadrumanous animal Troglodytes gorilla of Savage from Gaboon 

 in Africa, Dr. Jeffries Wyman 1 found the mean capacity, measured 

 according to the method employed by Dr. Morton, to be 28*9J cubic 

 inches, or considerably less than one-half the mean of the Hottentots 

 and Australians, who afford the minimum average for the human family. 

 The mean cranial capacity of three adult Chimpanzees was even less, or 

 24 cubic inches. 



Wrisberg and Sommering 2 proposed another point of comparison 

 the ratio of the mass of the encephalon to that of the rest of the 

 nervous system; and they asserted, that in proportion as any animal 

 possesses a larger share of the former; or, in other words, in proportion 

 as the percipient and intellectual organ exceeds the other or the organ 

 of the external senses the mental sphere may be expected to be more 

 diversified and developed. But although man is, in general, pre-eminent 

 in this respect, he is not absolutely so. It would be still more important 



to know the ratio, which the cere- 

 brum or brain proper bears to 

 the cerebellum and medulla ob- 

 longata. The first is essentially 

 the organ of intellect; and the 

 most striking character of the 

 human brain is the large deve- 

 lopement of the cerebral hemi- 

 spheres, of which we have no 

 parallel in the animal kingdom. 

 The last is the encephalic part in 

 which the nerves of sense arise 

 or terminate. 



The assertion, that man has 

 the largest cerebrum in propor- 

 tion to the cerebellum, is not ac- 

 curate. The Wenzels 3 found the 

 ratio, in him, to be as G/^g or 

 8 T 4 5 2 T to 1; in the horse, 4J to 1; 

 in the cow, 5 Jff to 1 ; in the dog, 

 6 2 4 s to 1; in the cat, 4 T 4 g to 1; 

 in the mole, 3| to 1 ; and in the 

 mouse, 6-f to 1. Nor is it true 

 that man has the largest cere- 

 Facial Line and Angle of Man. brum in proportion to the medulla 



1 A description of two additional Crania of the Enge-ena, &c., read before the Boston 

 Society of Natural History, Oct. 3, 1849; and published in the American Journal of Science 

 and Arts, second series, vol. ix. 



2 Corpor. Human. Fabric, iv. 92 ; and Blumenbach's Comp. Anat. by Lawrence, p. 292, 

 Lond., 1807. 



3 De Penitiori Structur. Cerebr. Hominis et Brutorum, tab. iv. 



