THE EVOLUTION OF THE BRAIN 

 By G. Elliott Smith 



Professor oj Afiatotny in the University oj London 



In ancient times, before paper or good parchment was 

 easy to obtain, writers used the leaves of old manuscripts 

 again and again after attempting to erase the writing already 

 inscribed on them. On examining one of these palimpsests, 

 as they are called, the modern student may be able to read 

 sufficient of its partly erased writing to decipher the story it 

 told. The human body is a palimpsest, which has preserved 

 in its every part the records of its inheritance, so that any- 

 one who carefully studies its structure and compares it with 

 the bodies of other living creatures can read the history of 

 man written in imperishable symbols in its very texture. 

 Seen in this light the structure of every bone and muscle, 

 the arrangement of the blood vessels and nerves, the consti- 

 tution of the organs of body, indeed, the nature of every 

 tissue of the organism, proclaim the fact that, wonderfully 

 as each and every part seems to have been designed to per- 

 form its particular function, it is really a readaptation of an 

 organ or tissue that may originally have served a useful pur- 

 pose very different from that which it serves now. Like the 

 ancient palimpsests, the human body has been inscribed 

 again and again with new devices that have only partly 

 obscured the more ancient writings. Let us take two illus- 

 trations: 



1. At a certain stage in the normal development of a 



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