404 THE SENSORIAL FUNCTIONS. 



of combining ideas, and of retaining them in the memory, 

 the greater do we find the development of the cerebral he- 

 mispheres. These parts of the brain are comparatively 

 small, as we have seen, in fishes, reptiles, and the greater 

 number of birds; but in the mammalia they are expanded in 

 a degree nearly proportional to the extent of memory, sa- 

 gacity and docility. In man, in whom all the faculties of 

 sense and intellect are so harmoniously combined, the brain 

 is not only the largest in size, but beyond all comparison the 

 most complicated in its structure.* 



A large brain has been bestowed on man, evidently with 

 the design that he should exercise superior powers of intel- 

 lect; the great distinguishing features of which are the ca- 

 pacity for retaining an immense variety of impressions, and 

 the strength, the extent, and vast range of the associating 

 principle, which combines them into groups, and forms them 

 into abstract ideas. Yet the lower animals also possess their 

 share of memory, and of reason: they are capable of ac- 

 quiring knowledge from experience; and, on some rare oc- 

 casions, of devising expedients for accomplishing particular 

 ends. But still this knowledge and these efforts of intellect 

 are confined within very narrow limits; for nature has as- 

 signed boundaries to the advancement of the lower animals, 

 which they can never pass. If one favoured individual be 

 selected fora special education, some additional share of in- 

 telligence may, perhaps, with infinite pains, be infused; but 

 the improvement perishes with that individual, and is wholly 

 lost to the race. By far the greater portion of that know- 

 ledge which it imports them to possess is the gift of nature, 

 who has wisely implanted such instinctive impulses as are 

 necessary for their preservation. Man, also, is born with 

 instincts, but they are few in number, compared with those 



* All the parts met with in the brain of animals exist also in the brain of 

 man; while several of those found in man are either extremely small, or alto- 

 gether absent in the brains of the lower animals. Soemmemng has enu- 

 merated no less than fifteen material anatomical differences between the hu- 

 man brain and that of the ape. 



