VOL. XLIX, NO. 



S8lT 



THE 



AMERICAN 

 NATURALIST 



A MONTHLY JOURNAL 

 Devoted to tie Advancement of the Biological Sciences with 

 Special Reference to the Factors of Evolution 



I. The Significance of Certain Internal Conditions of the Organism in Oi 



Evolution. Professor F. H. Pike and Dr. E. L. Scott - - 

 H. Correlation between Egg-laying Activity and YeUow Pigment in the D 



THE SCIENCE PRESS 

 ULNCASTER, PA. GARRISON, K. 1. 



NEW YORK: SUB-STATION 84 



