VOL XLTII, NO. 554 



FEBRUARY, 1913 



THE 



AMERICAN 

 NATURALIST 



A MONTHLY JOURNAL 

 Devoted to the Advancement of the Biological Science! 1 

 Special Eeference to the Factors of Evolution 



Adaptation thro 



NARD M. MET< 



Adaptation in 1 



- L»\\ . n ' e,T. Hi 



THE SCIENCE PRESS 

 LANCASTER, PA. OAERISON, R. ¥. 



HEW TORE: SUB-STATION 84 



