VOL. XLHI, NO. 607 



MARCH, 1909 



THE 



AMERICAN 

 NATURALIST 



A MONTHLY JOURNAL 

 Devoted to the Advancement of the Biological Sciences with 

 Special Reference to the Factors of Evolution 



CONTENTS 



p< 



Invitation Papers at the Baltimore Meeting of the Botanical Society of 

 America ; Darwin Memorial Session :— 

 Darwin as a Naturalist ; Darwin's Work on Cross Pollination in Plants. 



Professor WILLIAM TRELEASE 3 



Darwin's Influence upon Plant Geography and Ecology. Professor PEED- 



ERIC E. CLEMENTS ] 



Darwin's Work on Movement in Plants. Professor HERBERT MAULE 



It An Examination of Darwin's " Origin of Species " in the Light of Recent Ob- 

 servations and Experiments. Professor EDWIN LINTON. 183 



in. The Distinction between Development and Heredity in Inbreeding. Dr. 



EDWARD M. EAST 173 



IV. Breeding Experiments with Rats. . Professor T. H. MORGAN. 183 



The Chub and the Texas Horn Fly, Dr. Roy L. Moodik. ANei 

 the I^werMiwene of Nebraska, Harold James COOK . 



Heredity— The Chondriosomes as Bearers of th 

 Paynk. Cultural Bed Mutations in the Potato. 



THE SCIENCE PRESS 

 LANCASTER, PA. GARRISON, N. Y. 



NEW YORK : SUB-STATION 84 



