between
the margin and midrib.

[Illustration: Holly Fern. Polystichum Lonchitis (Nottawasaga, Canada,
West, Right, Alaska, Left) (Herbarium of C.E. Davenport)]

The name holly fern suggests its resemblance to holly leaves with their
bristle-tipped teeth. The specific name lonchitis (like a spear) refers to
its sharp teeth. A northern species growing in rocky woods from Labrador
to Alaska, and south to Niagara Falls, Lake Superior and westward. Its
southern limits nearly coincide with the northern limits of the Christmas
fern.

THE MARSH FERN TRIBE

Under this designation Clute has grouped three of the shield ferns, which
have a close family resemblance, and has thus distinguished them from the
wood ferns, which also belong to the shield fern family.

(1) THE MARSH FERN

_Aspidium thelypteris_. THELYPTERIS PALUSTRIS
_Dryopteris thelypteris. Nephrodium thelypteris_

[Illustration: The Marsh Fern]

These are all good names and each one is worthy to be chosen. _Aspidium_,
Greek for shield, in use for a century, adopted in all the seven editions
of Gray's Manual, is still the most familiar and pleasing term to its
friends. _Dryopteris_, Greek for oak fern, has been chosen by Underwood
and Britton and Brown and has grown in favor. _Nephrodium_, meaning
kidney-like, favored by Davenport, Waters and, of late, Clute, is a most
fitting name. THELYPTERIS, meaning lady fern, is found to be the earliest
name in use and according to rule the correct one.

[Illustration: The Marsh Fern. _Aspidium Thelypteris_]

Fronds pinnate, lanceolate, slightly or not at all narrowed at the base.
Pinnae horizontal or slightly recurved, linear-lanceolate and deeply
pinnatifid. Lobes obtuse, but appear acute when their margins are reflexed
over the sori. Veins once forked. Indusium minute. Stipes tall, lifting the
blades ten to fifteen inches above the mud, whence they spring.

The fronds of the marsh fern are apt to be sterile in deep shade. It may be
readily distinguished from the New York fern by its broad base, instead of
tapering to very small pinnae; by its long stalk, lifting the blade up into
the sunlight, and by the revolute margins of the fertile fronds, which have
suggested for it the name of "snuff-box" fern. It is separated from
the Massachusetts fern by its forked veins. Common in marshes and damp
woodlands; Canada to Florida and westward. While the marsh fern loves
moisture and shade it is sometimes found in dry,