vi PREFACE. 



tesy of the publishers of the ' Century Magazine ' who 

 have freely given me the use of their illustrations. To 

 Messrs. MauU and Fox and Messrs. Elliott and Fry I 

 am also indebted for their kindness in allowing me the 

 use of reproductions of their photographs. 



Francis Darwin. 



Cambridge, 



October, 1887. 



