PREFATORY^ NOTE. 



This Lecture gives results drawn from three 

 memoirs (a) The Influence of Parental Occupation 

 and Habit on the Welfare of the Offspring, by Ethel 

 M. Elderton, {p) The Influence of Unfavourable 

 Home Environment and Defective Physique on the 

 Intelligence of School Children, by David Heron, 

 and (f) A First Study of the Inheritance of Vision 

 and of the Relative Influence of Heredity and 

 Environment on Sight, by Amy Barrington and Karl 

 Pearson. The latter has been recently published 

 and the two former will shortly appear in the 

 Eugenics Laboratory Memoir Series. For further 

 details and discussion of results the reader is referred 

 to the above memoirs. 



CAMBRIDGE : PRINTED BY JOHN CLAY, M.A. AT THE UNIVERSITY PRESS. 



