AUTHOR'S PREFACE 



The author wishes to express her thanks to Miss 

 AUce M. Barton, an experienced teacher of nature 

 studies in the Boston pubUc schools, for reading the 

 completed manuscript and making valuable sugges- 

 tions. Thanks are due to Enos A. Mills, Dr. A. 

 Howard Clark, W. A. Bentley, Prof. Alexander 

 McAdie and the Blue Hill Observatory, Mrs. C. H. 

 McL. Burns, Rev. Joel H. Metcalf, Prof. E. S. Dana 

 and John Wiley and Sons, Inc., publishers of his 

 book; to the American Museum of Natural History, 

 United States Geological Survey, and many others 

 who have lent the photographs which are used in 

 the leaflets which accompany this volume; and to 

 the Comstock Publishing Company, Raymond and 

 Whitcomb Company and Ginn and Company for 

 the use of cuts. 



Cora Stanwood Cobb. 



Newton Upper Falls, Mass. 

 August, 1918 



