*]th January, 1903. 



Mr. J. Brown, F.R.S., President, in the Chair. 



HEREDITY IN ITS RELATION TO THE NERVOUS 

 SYSTEM. 



By John M. MacCormac, M.D., L.R.C.P. 8c S.Edin. 



(Abstract) 



In assuming that the mind of a child is devoid of character or 

 ideas, Locke attributed nothing to heredity. Man enters this 

 world -is a stranger, it is true, but he can investigate and 

 explore, and his mind is ever active to receive various per- 

 ceptions, and it is a matter of common observation that the 

 same objects produce different effects upon different minds. A 

 poet, painter or geologist looks at a landscape with entirely 

 different ideas. While the country lad knows every bird song 

 and the intricacies of every glade, the town-bred boy revels 

 in bricks and mortar and despises the dirty lanes. In all there 

 is a special quality, which responds to external perceptions, and 

 which is due to heredity. 



The broadest principle of heredity is, that like produces like, 

 that all the physiological and psychological characteristics of 

 the parent are transmitted to the child. Hence Darwin's 

 theory of Pangenesis, which supposes that every cell gives off 

 gemmules or germs, which permeating the whole body, and 



