VOL. XXXVII, NO. 438 



THE 



AMERICAN 

 NATURALIST 



A MONTHLY JOURNAL 

 DEVOTED TO THE NATURAL SCIENCES 

 IN THEIR WIDEST SENSE 



CONTENTS 



I. The Colors of Northern Gamopetalous Flowers . . - JOHN H. LOVELL 865 

 EE. The Causes of Acceleration and Betardation in the Metamorphosis of Ambly- 



stomatigrinum: a Preliminary Beport .... ■ J. H. POWERS 385 



in. The Origin of the Sporophyte .... Dr. BRADLEY MOOEE DAVIS 411 



IV. Notes and Literature : Zoogeography, The Atlantic Problem; Zoogeograph- 431 



ical Development of the Indo-Australian Archipelago — Botany, Influ- 434 



BOSTON, U. S. A. 



GINN & COMPANY, Publishers 



