VOL. XLIX, NO. 584 



AUGUST, 1915 



THE 



AMERICAN 

 NATURALIST 



A MONTHLY JOURNAL 

 Devoted to the Advancement of the Biological Science! with 



Special Reference to the Factors of Evolution 



f to Plant Breeders. Pro- 



THE SCIENCE PRESS 

 JLANOASTEE, FA. GARRISON, X. Y. 



NEW YORK : SUB-STATION 84 



