THE OLD AND THE NEW PHRENOLOGY. 



733 



animals certain regions of the brain can be mapped out and can 

 be assigned to the different senses. It has thus been proved that 

 in their action as well as in their structure the brains of man and 

 of animals are alike. 



If in structure and in function all brains are somewhat similar, 

 it may be interesting to obtain a little notion of what a brain is 

 really like. The figure will demonstrate this very well. 



Pig. 1.— Diagram of the External Surface of the Left Cerebral Hemisphere (modified 



from Ecker). 



It shows that the brain is an egg-shaped organ with an irregu- 

 lar surface of a yellowish - gray color. The irregularities are 

 formed by a folding of the surface layer so as to accommodate 

 itself to the small space in the head. To illustrate this, when a 

 handkerchief is spread out over the hands it takes up a great 

 space, and a box in order to hold it would have to be of large 

 size ; but by gathering the handkerchief up in the hands it is 

 thrown into folds, and, although its actual surface is not de- 

 creased, the space it occupies is much diminished, and it could 

 now be put in a very small box and yet all be there, but then its 

 surface would be irregular and show many creases. Now, what 

 was done to the handkerchief Nature has done to the brain as it 

 has developed. In the lower animals and in an early stage of life 

 the folds are few and simple, but in man when full grown they are 

 many and complex. This only means that the actual surface of 



