Vol. XI. Parts I and II 
November, 1915 
BIOMETRIKA 
A JOURNAL FOR THE STATISTICAL STUDY OF 
BIOLOGICAL PROBLEMS 
FOUNDED BY 
W. F. R. WELDON, FRANCIS GALTON and KARL PEARSON 
EDITED BY 
KARL PEARSON 
CAMBRIDGE UNIVERSITY PRES 
G. F. CLAY, Managee 
LONDON: FETTEK LANE, E.G. 
EDINBURGH : 100, PBINCBS STREET 
also 
H. K. LEWIS, 136, GOWBE STREET, LONDON, W.C 
WILLIAM WESLEY AND SON, 28, ESSEX STREET, LONDON, W.C. 
CHICAGO: UNIVERSITY OF CHICAGO PRESS 
BOMBAY, CALCUTTA AND MADRAS: MACMILLAN AND CO., LIMITED 
TORONTO : V J. M. DENT AND SONS, LIMITED 
TOKYO: THE MABUZEN-KABUSHIKI-KAISHA 
Price Twenty Shillings net 
[Issued December 22, 1915] 
