290 



Philosophy of Botany. 



transpiring ones. Such actions are walking, riding, singing, 

 speaking, piano playing, and almost all intellectual actions. 

 These acquired unconscious faculties are not transmissible to 

 descendants by inheritance, although this had been the process 

 by which instincts had originally been built up. 



The inherited mechanisms of instinct have, in the course 

 of evolution, been superseded by an organ of educability, the 

 evolution of the organs of the mind, the great hemispheres of 

 the brain. The annexed diagrams give a graphic illustration 

 of the gradual expansion and preponderance of the intellectual 

 over the vegetative, purely instinctive, reflex, and emotional 

 organs and functions. 



Comparative sketch of cerebral struct^ire of Fish, Reptile, B\rd, Mammal, 

 and Man, viewed laterally (A) and from above (B) ; of, olfactory ; cr, 

 hemispheres ; ol, corpus eallosum ; cb, cerebellum ; wi, medulla oblongata. 

 — After Le Conte. 



