THE MIGRATION OF BIRDS 



A CONSIDERATION OF HERR GATKE'S VIEWS 



BY 



F. B. 1WHITLOCK 



Author of " Birds of Derbyshire," <&c., <&c. 



(ALL EIGHTS RESERVED) 



3Lonfcon 



E. H. POETEE 

 7, PRINCES STREET, CAVENDISH SQUARE, W. 



1897 



