vi PREFACE 



racial evolution, to trace out the inter-relations of organic 

 rhythms and external periodicities. The ideal would be to 

 study the organismal drama of the year with the sympathetic 

 feeling of the old naturalists, such as Gilbert White, with 

 Darwin's dominant sense of correlation and evolution, and 

 with Spencer's grasp of the unity of science ! No one 

 knows better than myself how far my reach has exceeded 

 my grasp in this fascinating inquiry. Perhaps, however, 

 the book may give a stimulus to the serious study of 

 Phenology or Season-Lore. 



I am not forgetful that many naturalists have studied 

 the life of plants and animals in its varied seasonal ex- 

 pression, and that many of them have found the study so 

 rich in reward that they have sought to attract others to 

 it. From Gilbert White's evergreen Natural History of 

 Selborne to Professor L. C. Miall's Round the Year to 

 mention two books remarkable in their accuracy, insight, 

 and sincerity there has been a succession of Naturalist 

 Year-Books. But the aim of this volume is at once more 

 general and more intimate. It is an attempt to get at 

 the underlying principles. 



J. ARTHUR THOMSON. 



MARISCHAL COLLEGE, 



THE UNIVERSITY, ABERDEEN, 



April 1911. 



