VOL. XIII, NO. 496 



THE 



APRIL, 1908 



AMERICAN 

 NATURALIST 



A MONTHLY JOURNAL 

 DEVOTED TO THE NATURAL SCIENCES 

 IN THEIR WIDEST SENSE 



JOHNSON 217 



BESSEY 218 



The Taxonomic Aspect of the Species Question. Dr. NATHANIEL LORD 



BRITTON 225 



The Physiologic Aspect of the Species Question. Professor J. C. ARTHUR 243 



The Physiological Aspect of a Species. . . Dr. D. T. MacDOUGAL 249 

 An Ecologic View of the Species Conception. Professor FREDERIC E. 



CLEMENTS 253 



An Ecological Aspect of the Conception of Species. . Dr. H. C. COWLES 265 

 Discussion of the Species Question. Professor J. M. COULTER, Dr. J. B. 



POLLOCK, Professor T. J. BURRILL, E. G. HILL, Dr. G. H. SHULL, Dr. 



J. A. HARRIS, A. E. HITCHCOCK 272 



THE SCIENCE PRESS 

 LANCASTER, PA. GARRISON, N. Y. 



NEW YORK : SUB-STATION 84 



