VOL. XLI, NO. 490 



OCTOBEB, 1907 



THE 



AMERICAN 

 NATURALIST 



A MONTHLY JOURNAL 

 DEVOTED TO THE NATURAL SCIENCES 

 IN THEIR WIDEST SENSE 



CONTENTS 



AMADETIS W. GKABAU 607 

 n.2 Mutations and the Geographic Distribution of Nearly Belated Species in Plants 



and Animals J. A. ALLEN 653 



IIlANotes and Literature: Scientific Exhibits at the Seventh International Zoo- 

 logical Congress — Zoology; The families and genera of bats.— Birds 

 of North and Middle America.— Botany; Floral ecology . . .687 



BOSTON, U. S. A. 

 GINN & COMPANY, PUBLISHERS 

 29 BEACON STREET 



EnUred at the Pott-Omce, Boston, Matt., at Second-C 



