YOL. XLVI, NO. 542 



FEBRUARY, 1912 



THE 



AMERICAN 

 NATURALIST 



A MONTHLY JOURNAL 

 Devoted to the Advancement of the Biological Sciences with 

 Special Reference to the Factors of Evolution 



CONTENTS 



J 



f Cytology in Relation to the Study of Genetics. 



. The Correlation between Cfcromosomea tnd Particular Characters in Hy- 

 brid Echinoid Larv«e. - Professor David H. Tennent 

 Darwin's Theory of Evolution by the Selection of Minor Saltations. 



Professor HENRY FAIRFIELD OSBOBN 



The Color Sense of the Honey-bee ; The Pollination of Green Flowers. 



John H. Loveix 



r Articles and Discussion : Is the Change in the Sex Ratio of the Frog 

 t is affected by External Agents doe to Partial Fertilization. Professor 



THE SCIENCE PRESS 

 LANCASTER, PA. GARRISON, N. Y. 



NEW YORK : SUB-STATION 84 



