VOL X1VI, HO. 548 



AUOtTST, 1912 



THE 



AMERICAN 

 NATURALIST 



A MONTHLY JOURNAL 

 Devoted to the Advancement of the Biological Sciences with 

 Special Reference to the Factors of Evolution 



ft. Case of Polymorphism in Asplanchna simulating a 



binations is large. Dr. J. Akthtjb Harms 



lorter Articles and Discussion : The Production of Pnre Homozygotic Organ- 

 isms from Heterozygotes by Self-fertilization, Professor H. S. JraSBWW. 

 Yellow and Agonti Factors in Mice not "associated," C. C. Little. Physi- 

 cal Analogies of Biological Processes, Dr. O. F. Cook. On Fairness and 



rotes and Literature: Distribution and Origin of Life in America, T. 



LANCASTER, PA. GARRISON, H. Y. 



NEW YORK : SUB-STATION 84 



