of the mark.

We have appropriated from many sources such material as suited our purpose.
Our interest in ferns dates back to our college days at Amherst, when we
collected our first specimens in a rough, bushy swamp in Hadley. We found
here a fine colony of the climbing fern (_Lygodium_). We recall the slender
fronds climbing over the low bushes, unique twiners, charming, indeed, in
their native habitat. We have since collected and studied specimens of
nearly every New England fern, and have carefully examined most of the
other species mentioned in this book. By courtesy of the librarian, Mr.
William P. Rich, we have made large use of the famous Davenport herbarium
in the Massachusetts Horticultural library, and through the kindness of
the daughter, Miss Mary E. Davenport, we have freely consulted the larger
unmounted collection of ferns at the Davenport homestead, at Medford,[1]
finding here a very large and fine assortment of _Botrychiums_, including a
real _B. ternatum_ from Japan.

[Footnote 1: Recently donated to the Gray Herbarium.]

For numerous facts and suggestions we are indebted to the twenty volumes of
the _Fern Bulletin_, and also to its able editor, Mr. Willard N. Clute. To
him we are greatly obligated for the use of photographs and plates, and
especially for helpful counsel on many items. We appreciate the helpfulness
of the _American Fern Journal_ and its obliging editor, Mr. E.J. Winslow.
To our friend, Mr. C.H. Knowlton, our thanks are due for the revision of
the checklist and for much helpful advice, and we are grateful to Mr.
S.N.F. Sanford, of the Boston Society of Natural History, for numerous
courtesies; but more especially to Mr. C.A. Weatherby for his expert and
helpful inspection of the entire manuscript.