140 Brain : 



receiving, interpreting, and transmitting the aggregated 

 sensations of all the millions of individual cells of which 

 an animal organism is composed. 



I need not here review the evidences and the argument 

 by which it is now shown that sensory ganglia for per- 

 ception and reflex perception, grew up at the intersection 

 of the primary nerve filaments ; how the special sense 

 organs took form ; how at length the cerebellum came to 

 be lodged in the forward end of the pluricellular animal, 

 and how the ever-increasing need of greater capacity for 

 the sensory business of a world-roaming organism led to 

 that enormous superaddition to the cerebellam, known as 

 the cerebrum. 



What is designed here to point out is the fact that the 

 nervous system of the human organism, particularly the 

 cerebral portion of it, or, in other words, the tissue of 

 mind and intellect, has always been in the past and is to- 

 day a progressive tissue. It came into existence, as brain, 

 in response to a necessity on the part of the organism for 

 greater protoplasmic capacity, for the I'eception and util- 

 ization of intelligence. That necessity and that stimulus 

 still exist and grow constantly more urgent. 



Bone and muscle cells have developed to the extent of 

 the necessity which led to their differentiation ; the in- 

 centives to locomotion and organic support remain the 

 same, unchanged in character; hence, bone and muscle 

 cells long ago reached the acme of their development. 



