146 
THE DESCENT OF MAN. 
P-AET I. 
brate series. Dr. J. Barnard Davis has proved 70 bv 
many careful measurements, that the mean internal 
capacity of the skull in Europeans is 92‘3 cubic inches; 
in Americans 87‘5 ; in Asiatics 87T ; and in Australians 
only 8D9 inches. Professor Broca 71 found that skulls 
from graves in Paris of the nineteenth century, were 
larger than those from vaults of the twelfth century, in 
the proportion of 1 484 to 1426 ; and Prichard is per- 
suaded that the present inhabitants of Britain have 
“much more capacious brain-cases” than the ancient 
inhabitants. Nevertheless it must be admitted that 
some skulls of very high antiquity, such as the famous 
one of Neanderthal, are well developed and capacious. 
With respect to the lower animals, M. E. Lartet, 72 by com- 
paring the crania of tertiary and recent mammals, be- 
longing to the same groups, has come to the remarkable 
conclusion that the brain is generally larger and the 
convolutions more complex in the more recent form- 
On the other hand I have shewn 73 that the brains of 
domestic rabbits are considerably reduced in bulk, in 
comparison with those of the wild rabbit or hare ; and 
this may be attributed to their having been closely con- 
fined during many generations, so that they have exerted 
but little their intellect, instincts, senses, and voluntary 
movements. 
The gradually increasing weight of the brain and 
skull in man must have influenced the development of 
the supporting spinal column, more especiallv whilst 
he was becoming erect. As this change of position was 
70 ‘Philosophical Transactions,’ 1809, p. 513. 
71 Quoted in C. Vogt’s ‘Lectures on Man,’ Eng. translat. 1 864, p- 
88, 90. Prichard, ‘Phys. Hist, of Mankind, ’ vol. i. 1838, p. 305. 
72 ‘ Comptes Eendus des Seances,’ &c. June 1, 1868. 
73 ‘ The Variation of Animals and Tlants under Domestication,’ vol- 
i. p. 124-129. 
