(6) EBONY SPLEENWORT
Asplenium platynèuron. A. ebèneum
Fronds upright, eight to eighteen inches high, linear-lanceolate, the fertile ones much taller, and pinnate. Pinnæ scarcely an inch long, the lower ones very much shorter, alternate, spreading, finely serrate or incised, the base auricled. Sori numerous, rather near the midvein, stipe and rachis lustrous brown. ("Ebony.")
This rigidly upright but graceful fern flourishes in rocky, open woods, and on rich, moist banks, often in the neighborhood of red cedars. Having come upon it many times in our rambles, we should say it was not uncommon.
A lightly incised form of the pinnæ has been described as var. serratum. A handsome form discovered in Vermont in 1900 by Mrs. Horton and named Hortonæ (also called incisum) has plume-like fronds with the pinnæ cut into oblique lobes, which are coarsely serrate.
[Illustration: Ebony Spleenwort. Asplenium platyneuron (Melrose, Mass., G.E. Davenport)]
[Illustration: Bradley's Spleenwort. Asplenium Bradleyi a, from Maryland; b, from Kentucky (From Waters's "Ferns," Henry Holt & Co.)]
(7) BRADLEY'S SPLEENWORT. Asplenium Brádleyi
Fronds oblong-lanceolate, pinnate, three to ten inches long. Pinnæ oblong-ovate, obtuse, incised or pinnátifid into oblong, toothed lobes. The basal pinnæ have broad bases, and blunt tips and are slightly stalked. Stipes and rachis dark brown and the sori short, near the midrib.
A rare and beautiful fern growing on rocks preferring limestone and confined mostly to the southern states. Newburg, N.Y., to Kentucky and Alabama, westward to Arkansas.
(8) MOUNTAIN SPLEENWORT. Asplenium montanum
Fronds ovate-lanceolate from a broad base, two to eight inches long, somewhat leathery, pinnate. Pinnæ ovate-oblong, the lowest pinnately cleft into oblong or ovate cut-toothed lobes, the upper ones less and less divided. Rachis green, broad, and flat.
[Illustration: Mountain Spleenwort (From the "Fern Bulletin")]
Small evergreen ferns of a bluish-green color, growing in the crevices of rocks and cliffs. Connecticut to Ohio, Kentucky, Arkansas and southwest. July. Rare. Williams, in his "Ferns of Kentucky," says of this species, "Common on all sandstone cliffs and specimens are large on sheltered rocks by the banks of streams."
(9) RUE SPLEENWORT. Asplenium Ruta-murària
Fronds evergreen, small, two to seven inches long, deltoid-ovate, two to three pinnate below, simply pinnate above, rather leathery in texture. Divisions few, stalked, from cuneate to roundish-ovate, toothed or incised at the apex. Veins forking. Rachis and stipe green. Sori few, soon confluent.
[Illustration: The Rue Spleenwort. A. Ruta-muraria (Top, Lake Huron--Lower Left, Mt. Toby, Mass.--Lower Right, Vermont) (From Herbarium of Geo. E. Davenport)]
This tiny fern grows from small fissures in the limestone cliffs, and is rather rare in this country; but in Great Britain it is very common, growing everywhere on walls and ruins. From Mt. Toby, Mass., and Willoughby Mountain, Vt., to Michigan, Missouri, Kentucky and southward.
[B. THE LARGE SPLEENWORTS. Athýrium]
The following species, which are often two to three feet high and grow in rich soil, are quite different in appearance and habits from the small rock spleenworts just described. Some botanists have kept them in the genus Asplenium because their sori are usually rather straight or only slightly curved, but others are inclined to follow the practice of the British botanists and put them into a separate group under Athýrium. Nearly all agree that the lady fern, with its variously curved sori, should be placed here, and many others would place the silvery spleenwort in the same genus, partly because of its frequently doubled sori. In regard to the last member of the group, the narrow-leaved spleenwort, there is more doubt. The sori taken separately would place it with the Aspleniums, but considering its size, structure, habits of growth and all, it seems more closely allied to the two larger ferns than to the little rock species. We shall group the three together as the large spleenworts, or for the sake of being more definite adopt Clute's felicitous phrase.
THE LADY FERN AND ITS KIN
1. THE LADY FERNS
Fronds one to three feet high, broadly lanceolate, or ovate-oblong, tapering towards the apex, bipinnate. Pinnæ lanceolate, numerous. Pinnules oblong-lanceolate, cut-toothed or incised. Fruit-dots short, variously curved. Indusium delicate, often reniform, or shaped like a horseshoe, in some forms confluent at maturity.
Widely distributed, common and varying greatly in outline. The newer nomenclature separates the lady fern of our section into two distinct species, which should be carefully studied.[A]
[Footnote A: See monograph by F.K. Butters in Rhodora of September, 1917.]
(1) THE UPLAND LADY FERN. ATHÝRIUM ANGÚSTUM
Asplènium Fìlix-femina
The rootstock or rhizome of the Upland Lady Fern here pictured shows how the thick, fleshy bases of the old fronds conceal the rootstock itself. In the Lowland Lady Fern the rootstock is but slightly concealed by old stipe bases, and so may be distinguished from its sister fern.
One design of such rootstocks is to store up food (mostly starch), during the summer to nourish the young plants as they shoot forth the next spring. The undecayed bases of the old stipes are also packed with starch for the same purpose.
[Illustration: Rootstock of the Upland Lady Fern]
[Illustration: The same split lengthwise (From Waters's "Ferns," Henry Holt & Co.)]
[Illustration: Sori of Lady Fern. Athyrium angustum]
Rootstocks horizontal, quite concealed by the thick, fleshy bases of old fronds. Scales of the long, tufted stipes dark brown. Indusium curved, often horseshoe-shaped, usually toothed or fringed with fine hairs, but without glands. Fronds bipinnate, one to three feet high, widest near the middle.
This is the common species of northern New England and the Canadian Provinces. The fronds differ very widely in form and a great many varieties have been pointed out, but the fern student, having first learned to identify the species, will gradually master the few leading varieties as he meets them.
Those growing in warm, sunny places where the fruit-dots when mature incline to cover the whole back of the frond are called "sun forms." These are varieties TÝPICUM and ELÀTIUS, both with the pinnæ obliquely ascending (including variety angustum of D.C. Eaton), but the latter has broader fronds with the pinnules of the sterile fronds oblong-lanceolate, somewhat acute and strongly toothed or pinnatifid.
[Illustration: Varieties of Lady Fern Left to right--lst and 2nd, Var. typicum; 3d, elatius; 4th, rubellum; 5th, uncertain, perhaps confertum]
Var. RUBÉLLUM has the sori distinct even when mature; its pinnules stand at a wide angle from the rachis of the pinna and are strongly toothed or pinnatifid with obtuse teeth. This variety favors regions with cool summers, or dense shade in warmer regions. The term RUBÉLLUM alludes to the reddish stems so often seen but this sign alone may not determine the variety. It occurs throughout the range of the species, being a common New England fern. Fernald remarks that this is also a common form of the species in southern Nova Scotia.
Among other varieties named by Butters are CONFÉRTUM, having the pinnules irregularly lobed and toothed; joined by a membranous wing, the lobes of the pinnules broad and overlapping, giving the fern a compact appearance; LACINIÀTUM with pinnules very irregular in size and shape, with many long, acute teeth, which project in various directions. "An abnormal form which looks as if it had been nibbled when young."
These varieties are represented in the Gray Herbarium.
(2) THE LOWLAND LADY FERN
ATHÝRIUM ASPLENIÒIDES
Rootstocks creeping, not densely covered with the persistent bases of the fronds. Stipes about as long as the blade. Scales of the stipe very few, seldom persistent, rarely over 3-16 of an inch long. Fronds narrowly deltoid, lanceolate, widest near the base, the second pair of pinnæ commonly longest. Indusia ciliate, the cilia (hairs) ending in glands. Spores dark, netted or wrinkled.
[Illustration: Lowland Lady Fern. ATHYRIUM ASPLENIOIDES (From the Gray Herbarium)]
The following two forms are named by Butters:
F. TÝPICUM. The usual form frequent in eastern Massachusetts, Rhode Island, Connecticut, New York, Pennsylvania, North Carolina, Ohio, and Missouri.
F. SUBTRIPINNÀTUM. An unusually large and rare form with triangular, lanceolate, and pinnatifid pinnules, having blunt, oblong segments. Wet situations in half shade. Massachusetts, West Virginia, and Virginia.
Our lowland or southern lady fern flourishes in the southern states, comes up the Atlantic Coast until it meets the upland or northern species in Pennsylvania and southern New England, and their identification can hardly fail to awaken in the student a keen interest.
Our American botanists are inclined to think that the real Athýrium fìlix-fémina is not to be found in the northeastern United States, but is rather a western species, with its habitat in California and the Rocky Mountain region and identical with Athýrium cyclosòrum.
But whatever changes may occur in the scientific name of the old Athýrium fìlix-fémina, the name lady fern will not change, but everywhere within our limits it will hold its own as a familiar term.
Underwood, writing of the lady fern under the genus Asplenium, mentions the form "exìle, small, starved specimens growing in very dry situations and often fruiting when only a few inches high." He also mentions Eaton's "angústum," and alludes to the "Remaining sixty-three varieties equally unimportant that have been described of this species."
The lady fern is common in moist woods, by walls and roadsides, and at its best is a truly handsome species, although, like Mrs. Parsons, we have noticed that in the late summer it loses much of its delicacy. "Many of its forms become disfigured and present a rather blotched and coarse appearance." The lady fern has inspired several poems, which have been quoted more or less fully in the fern books. The following lines are from the pen of Calder Campbell:
"But not by burne in wood or dale Grows anything so fair As the palmy crest of emerald pale Of the lady fern when the sunbeams turn To gold her delicate hair."
Referring, perhaps, to the fair colors of the unfolding crosiers revealing stipes of a clear wine color in striking contrast with the delicate green of the foliage.
In identifying this fern the novice should bear in mind the tendency of the curved sori of youth to become straightened and even confluent with age, although such changes are rather unreliable. Possibly the suggestion of the poetic Davenport may be helpful to some that there is "An indefinable charm about the various forms of the lady fern, which soon enables one to know it from its peculiarly graceful motion by merely gently swaying a frond in the hand." Spores ripen in August.
The lady fern is very easy to cultivate and when once established is apt to crowd aside its neighbors.
(3) SILVERY SPLEENWORT. ATHÝRIUM ACROSTICHÒIDES
Asplènium acrostichòides. Asplènium thelypteròides
Fronds two to four feet tall, pinnate, tapering both ways from the middle. Pinnæ deeply pinnatifid, linear-lanceolate, acuminate. Lobes oblong, obtuse, minutely toothed, each bearing two rows of oblong or linear fruit-dots. Indusium silvery when young.
[Illustration: Silvery Spleenwort. Athyrium acrostichoides]
[Illustration: Silvery Spleenwort. Athyrium acrostichoides]
The sterile fronds come up first and the taller, fertile ones do not appear until late in June. Where there are no fruit-dots the hairs on the upper surface of the fronds will help to distinguish it from specimens of the Marsh fern tribe, which it somewhat resembles. The regular rows of nearly straight, clear-cut sori of the fertile fronds are very attractive, and the lower ones, as well as those at the slender tips of the pinnæ, are frequently double.
Rich woods and moist, shady banks, New England to Kentucky and westward. Generally distributed but hardly common.
(4) NARROW-LEAVED SPLEENWORT
ATHÝRIUM ANGUSTIFÒLIUM. Asplenium angustifòlium
Fronds one to four feet tall, pinnate. Pinnæ numerous, thin, short-stalked, linear-lanceolate, acuminate, those of the fertile fronds narrower. Fruit-dots linear. Indusium slightly convex.
[Illustration: Narrow-leaved Spleenwort. Athyrium angustifolium (Vermont) (Geo. E. Davenport)]
In rich woods from southern Canada and New Hampshire to Minnesota and southward. September. Not common. Mt. Toby, Mass., Berlin and Meriden, Conn., and Danville, Vt. Can be cultivated but should not be exposed to severe weather, as its thin and delicate fronds are easily injured. Woolson writes of it, "There is nothing in the fern kingdom which looks so cool and refreshing on a hot day as a mass of this clear-cut, delicately made-up fern."
[Illustration: Pinnæ and Sori of Athyrium angustifolium]
[HART'S TONGUE]
Scolopéndrium. PHYLLÌTIS
Sori linear, a row on either side of the midvein, and at right angles to it, the indusium appearing to be double. (Scolopendrium is the Greek for centipede, whose feet the sori were thought to resemble. Phyllitis is the ancient Greek name for a fern.) Only one species in the United States.
| (1) Scolopendrium vulgàre PHYLLÌTIS SCOLOPÉNDRIUM Fronds thick and leathery, oblong-lanceolate from an auricled, heart-shaped base, ten to twenty inches long and one to two inches wide. Margin entire, bright green. | |
| [Illustration: Sori of Scolopendrium vulgare] |
In shaded ravines under limestone cliffs. Chittenango Falls, and Scolopendrium Lake, central New York, and Tennessee. Also, locally in Ontario and New Brunswick. One of the rarest of our native ferns, although very common in Great Britain. This plant is said to be easily cultivated, and to produce numerous varieties. According to Woolson, "No rockery is complete without the Hart's Tongue, the long, glossy, undulating fronds of which are sufficiently unique to distinguish any collection." In cultivation it "needs light protection through the winter in northern New England."
[Illustration: Hart's Tongue. Scolopendrium vulgare (Base of calcareous rocks, Owen Sound, Ontario, Canada)]