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.

The illustrations have been carefully selected; many of them from original
negatives bequeathed to the author by his friend, Henry Lincoln Clapp,
pioneer and chief promoter of school gardens in America. Some have been
photographed from the author's herbarium, and from living ferns. A few
are from the choice herbarium of Mr. George E. Davenport, and also a few
reprints have been made from fern books, for which due credit is given. The
Scott's spleenwort, on the dedication page, is reprinted from Clute's "Our
Ferns in Their Haunts."

INTRODUCTION

Thoreau tells us, "Nature made a fern for pure leaves." Fern leaves are in
the highest order of cryptogams. Like those of flowering plants they are
reinforced by woody fibres running through their stems, keeping them erect
while permitting graceful curves. Their exquisite symmetry of form, their
frequent finely cut borders, and their rich shades of green combine to make
them objects of rare beauty; while their unique vernation and method of
fruiting along with their wonderful mystery of reproduction invest them
with marked scientific interest affording stimulus and culture to the
thoughtful mind. By peculiar enchantments these charming plants allure the
ardent Nature-lover to observe their haunts and habits.

"Oh, then most gracefully they wave
In the forest, like a sea,
And dear as they are beautiful
Are these fern leaves to me."

As a rule the larger and coarser ferns grow in moist, shady situations, as
swamps, ravines, and damp woods; while the smaller ones are more apt to be
found along mountain ranges in some dry and even exposed locality. A tiny
crevice in some high cliff is not infrequently chosen by these fascinating
little plants, which protect themselves from drought by assuming a mantle
of light wool, or of hair and chaff, with, perhaps, a covering of white
powder as in some cloak ferns--thus keeping a layer of moist air next to
the surface of the leaf, and checking transpiration.