THE CEREBRUM IX DIFFERENT RACES, ETC. 341 



a number of observations made upon the brains of elephants, 

 in which the weights ranged from nine to ten pounds. 1 

 Rudolphi gives the weight of the encephalon of a whale, 

 seventy-five feet long, as considerably over five pounds. 2 

 With the exception of these animals, man possesses the 

 largest brain in the zoological scale. 



Another interesting point in this connection is the de- 

 velopment of cerebral convolutions in certain animals, by 

 which the relative amount of gray matter is increased. In 

 fishes, reptiles, and birds, the surface of the hemispheres is 

 smooth ; but in many mammalia, especially in those remark- 

 able for intelligence, the cerebrum presents a greater or less 

 number of convolutions, as it does in the human subject. 3 



Comparing the relative size of the brain, its complexity 

 of organization, and the increase of its gray substance by 

 convolutions, with the development of intelligence in the 

 animal scale, it is so evident that the cerebrum is the seat of 

 the intellectual faculties, that this point in our argument 

 seems to need no farther discussion. 



Development of the Cerebrum in Different Races of 

 and in Different Individuals. It may be stated as a general 

 proposition, that in the different races of men, the cerebrum 

 is developed in proportion to their intellectual power ; and 

 in different individuals of the same race, the same general 

 rule obtains. Still, this law presents marked exceptions. 

 Certain brains in an inferior race may be larger than the 

 average in the superior race ; and it is frequently observed 

 that unusual intellectual vigor is coexistent with a small 

 brain, and the reverse. These exceptions, however, do not 

 take away from the force of the original proposition. As 



1 TODD, Cydopcedia of Anatomy and Physiology, London, 1839-'47, vol. iii., 

 p. 664, Article, Nervous Centres. 



8 RUDOLPHI, Grundlss der Physiologic, Berlin, 1823, Bd. ii., Erste Abthei- 

 lung, S. 12. 



3 VAX DER HOEVEN, Handbook of Zoology, Cambridge, 1858, vol. ii., pp. 42, 

 227, 358, 596. 



