PREFACE. IX 



things are quoted from the incomparable descriptions of Bige- 

 low. I am under obligations to Dr. Gray for suggestions in 

 regard to the distribution into families and genera ; but I should 

 be sorry, to have him considered responsible for any thing 

 in its execution. Mr. Oakes has furnished me with many 

 beautiful specimens, such as nobody else can make. To Mr. 

 Russell, I am indebted for a communication upon the Pitch 

 Pine, and for other favors, as well as for the catalogue of 

 Mosses. To my friends, Messrs. E. Tuckerman and B. D. 

 Greene, I owe thanks for the use of specimens from their exten- 

 sive herbaria. Dr. Barratt, of Middletown, Conn., has given me 

 important assistance in the study of the Poplars and Willows ; 

 and from the invaluable Report of my friend Dr. Harris, I 

 have, with his consent, obtained much information, not to be 

 found elsewhere, in regard to insects. 



To so many citizens of the Commonwealth am I indebted 

 for aid received in conducting the Survey and ascertaining the 

 condition of the forests, that I can do no more than mention 

 their names. From Hon. D. P. King and Messrs. S. P. Fowler, 

 of Danvers ; Josiah Newhall, of Lynnfield, and Lilley Eaton, of 

 South Reading ; J. L. Lewis, of Hingham, Samuel A. Turner, 

 of South Scituate, and my friend G. P. Bradford, then of Ply- 

 mouth ; from Messrs. Chester Adams, of South Natick, and 

 Daniel Adams, 3d, of Newbury ; Daniel Davis, of Fairhaven, 

 Thomas A. Greene, of New Bedford, and Hezekiah Barnard, 

 of Nantucket ; S. Davis, of Truro, Solomon Freeman, of Brews- 

 ter, and E. Swift, of Falmouth ; from Messrs. Jabez Newel, and 

 Abijah M. Ide, of South Attleborough ; Rhodolphus Sanderson, 

 of East Whately, and D. Willard, of Greenfield: C. B. Rising, 

 of Worthington, and Joseph Field, of Charlemont; C. S. Dar- 

 ling, of Gill, and Samuel Mixter, of New Braintree ; Allen C. 

 Metcalf, of Lenox, J. H. Cobb, of Dedham, and S. Salisbury, 

 of Worcester ; from Henry Colman, of the Agricultural Sur- 

 vey, and especially from Wm. Bacon, of Richmond, Austin 

 Bacon, of Natick, and Henry W. Cushman, of Bernardston, 

 I received very useful letters, — from the three latter gentlemen, 

 communications of great value. 



From Messrs. P. T. Jackson, N. Hale, Ch. L. Storrow, B. T. 



