PISCES. 19 



against the attacks of their adversaries. To the varying functions of different organs, 

 therefore, the nervous system is appropriately adapted. When the sense of smelling 

 is most conducive to their convenience, there is a more capacious nose, large olfactory 

 nerves, and larger anterior lobes of the brain ; and when seeing is more advantageous, 

 the anterior lobes are smaller, and the olfactory nerves decrease in the same ratio, 

 the eyes are consequently large, and the optic nerves and parts of the brain from 

 which they originate are commensurate with them. Besides the different form and 

 size of the several portions of the brain generally existing, it is furnished with 

 additional lobes when modified powers are necessary. 



D 2 



