B. INDUSIUM PRESENT
| 1. Sori on the edge of a pinnule terminating a vein; sporangia at the base of a long, bristle-like receptacle surrounded by a cup-shaped indusium. Filmy Fern. Trichomanes. |
| 2. Indusium formed by the reflexed margin of the pinnules. (1) Sporangia on a continuous line; fronds large, ternate; indusium narrow. Bracken. Brake. Pteris. |
| (2) Sporangia in oblong sori under a reflexed tooth of a pinnule; indusium broad; rachis dark and shining. Maidenhair. Adiantum. |
| (3) Sori in roundish or elongated masses. Indusium broad, nearly continuous, fronds mostly smooth, somewhat leathery, pinnate. Rock species. Cliff brakes. Pellæa. |
| Indusium narrow, seldom continuous, formed by the margin of separate lobes or of the whole pinnules; often inconspicuous, fronds usually hairy. Lip Ferns. Cheilanthes. |
| Indusium of the reflexed edges, at first reaching to the midrib, or nearly so; later opening out nearly flat; fruiting pinnules pod-like; sterile fronds broad. Rock brakes. Cryptogramma. |
| 3. Indusium never formed of the margin of the frond. Sori various. (1) Fruit-dots oblong, parallel with the midrib, somewhat sunken in the tissues of the frond. Water-loving species. Chain Ferns. Woodwardia. |
| (2) Fruit-dots and indusium roundish. Indusium shield-shaped, fixed by the center. Evergreen glossy ferns in rocky woods. Shield Ferns. Polystichum. |
| Indusium cordate, fixed by the sinus. Wood Ferns. Aspidium. |
| Indusium hood-shaped, fixed centrally behind the sorus and arching over it, soon withering, often illusive. Fronds two to three pinnate, very graceful. Moisture-loving species. Bladder Ferns. Cystopteris. |
| Indusium star-shaped, of a few irregular segments fixed beneath the sorus, often obscure. Mostly small, rock-loving plants, usually rather chaffy, at least at the base, and growing in tufts. Woodsia. |
| Indusium cup-shaped, fixed beneath the sorus, supported by the tooth of a leaf; sporangia borne in an elevated, globular receptacle open at the top. Fronds finely cut. Hayscented Fern. Dennstædtia. |
| (3) Fruit-dots and indusium linear. (But see Athyrium.) Very long, nearly at right angles to the midrib, double; blade thick oblong-lanceolate, entire; heart-shaped at the base. Hart's Tongue. Scolopendrium. |
| Shorter and irregularly scattered on the under side of the frond, some parallel to the midrib, others oblique to it, and often in pairs or joined at the ends; blade tapering to a slender tip. Walking Fern. Camptosorus. |
| Short, straight, mostly oblique to the midrib. Indusium rather narrow, opening toward the midrib, fronds lobed or variously divided. Spleenworts. Asplenium. |
| Short, indusium usually more or less curved and frequently crossing a vein. The large spleenworts including Lady Fern. Athyrium. |
[DESCRIPTIVE TEXT OF THE FERNS]
In this manual our native ferns are grouped scientifically under five distinct families. By far the largest of these groups, and the first to be treated, is that of the real ferns (Polypodiàceæ) with sixty species and several chief varieties. Then follow the flowering ferns (Osmundàceæ) with three species; the curly grass and climbing ferns (Schizæàceæ) with two species; the adder's tongue and grape ferns (Ophioglossàceæ) with seven species; and the filmy ferns (Hymenophyllàceæ) with one species.
Corresponding with these five families, the sporangia or spore cases of ferns have five quite distinct forms on which the families are founded.
Fig. 1-4: Sporangia of the Five Families]
1. The Fern Family proper (Polypodiàceæ) has the spore cases stalked and bound by a vertical, elastic ring (Fig. 1). The clusters of fruit-dots containing the spore cases may be open and naked as in polypody (Fig. 2), or covered by an indusium, as in the shield ferns (Fig. 3).
2. The Royal Fern Family (Osmunda) has the spore cases stalked with only a rudimentary ring on one side, which opens longitudinally (Fig. 4).
3. The Climbing Fern Family (Lygodium, Schizæa) has the spore cases sessile in rows; they are small, nut-like bodies with the elastic ring around the upper portion (Fig. 5).[1]
[Footnote 1: These figures are enlarged.]
4. The Adder's Tongue Family (Ophioglóssum, Botrýchium) has simple spore cases without a ring, and discharges its spores through a transverse slit (Fig. 6).
5. The Filmy Fern Family (Trichómanes) has the spore cases along a bristle-like receptacle and surrounded by an urn-shaped, slightly two-lipped involucre; ring transverse and opening vertically (Fig. 7).
Fig. 5-7: Indusium
THE FERN FAMILY PROPER OR REAL FERNS
POLYPODIÀCEÆ
Green, leafy plants whose spores are borne in spore-cases (sporangia), which are collected in dots or clusters (fruit-dots or sori) on the back of the frond or form lines along the edge of its divisions. Sporangia surrounded by vertical, elastic rings bursting transversely and scattering the spores. Fruit-dots (sori) often covered, at least when young, by a membrane called the indusium. Spores brown.
[THE POLYPODIES]
1. POLYPODY. Polypodium
(From the Greek meaning many-footed, alluding to the branching rootstocks.)
Simple ferns with stipes articulated to the creeping rootstocks, which are covered with brown, chaffy scales. Fruit-dots round, naked, arranged on the back of the frond in one or more rows each side of the midrib. Sporangia pedicelled, provided with a vertical ring which bursts transversely. A large genus with about 350 species, widely distributed, mostly in tropical regions.
(1) COMMON POLYPODY. Polypodium vulgare
Fronds somewhat leathery in texture, evergreen, four to ten inches tall, smooth, oblong, and nearly pinnate. The large fruit-dots nearly midway between the midrib and the margin, but nearer the margin.
Common Polypody. Polypodium vulgare
| Common everywhere on cliffs, usually in half shade, and may at times spring out of decaying logs or the trunks of trees. As the jointed stipes, harking back to some ancient mode of fern growth, fall away from the rootstocks after their year of greenness, they leave behind a scar as in Solomon's seal. The polypody is a gregarious plant. By intertwining its roots the fronds cling together in "cheerful community," and a friendly eye discovers their beauty a long way off. August. Abounds in every clime, including Europe and Japan. In transplanting, sections should be cut, not pulled from the matted mass. Var. cambricum has segments broader and more or less strongly toothed. Var. cristatum has the segments forked at the ends. Several other forms are also found. Fruited Frond |
| The Common Polypody. Polypodium vulgare (Photographed by Miles Greenwood, Melrose, Mass.) |
(2) GRAY OR HOARY POLYPODY
Polypodium incànum. P. polypodiòides
Fronds oblong, two to seven inches long, deeply pinnátifid, gray and scurfy underneath with peltate scales having a dark center. Fruit-dots rather small, near the margin and obscured by the chaff.
Gray or Hoary Polypody. Polypodium incanum
In appearance the gray polypody is much like the common species, as the Greek ending oides (like) implies. In Florida and neighboring states it often grows on trees; farther north mostly on rocks. Reported as far north as Staten Island. It is one of the "resurrection" ferns, reviving quickly by moisture after seeming to be dead from long drouth. July to September. Widely distributed in tropical America. Often called Tree-Polypody.
[THE BRACKEN GROUP]
Sporangia near or on the margin of the segments, the reflexed portions of which serve as indusia.
[1. BRACKEN OR BRAKE]
Ptèris aquilina. PTERÍDIUM LATIÚSCULUM[1]
[Footnote 1: The use of small capitals in the scientific names indicates in part the newer nomenclature which many botanists are inclined to adopt.]
Fronds broadly triangular, ternate, one to three feet high or more, the widely spreading branches twice pinnate, the lower pinnules more or less pinnátifid. Sporangia borne in a continuous line along the lower margin of the ultimate divisions whose reflexed edges form the indusium. (Greek, pteron, a wing, the feathery fronds suggesting the wings of a bird.)
Common Bracken or Brake, a Sterile Frond. Pteris aquilina (Providence County, R.I.)
A Fertile Frond of Common Bracken. Pteris aquilina (Suffolk County, Mass.)
"The heath this night must be my bed,
The bracken curtain for my head."
SCOTT.
The outlines of the young bracken resemble the little oak fern. It flourishes in thickets and open pastures, often with poor soil and scant shade. It is found in all parts of the world, and is said to be the most common of all our North American ferns. In a cross section of the mature stipe superstition sees "the devil's hoof" and "King Charles in the oak," and any one may see or think he sees the outlines of an oak tree. It was the bracken, or eagle fern, as some call it, which was supposed to bear the mysterious "fern seed," but only on midsummer eve (St. John's eve).
"But on St. John's mysterious night,
Confest the mystic fern seed fell."
This enabled its possessor to walk invisible.
"We have the receipt for fern-seed,
We walk invisible."
SHAKESPEARE.
The word brake or bracken is one of the many plant names from which some of our English surnames are derived, as Brack, Breck, Brackenridge, etc., and fern (meaning the bracken) is seen in Fern, Fearns, Fernham, Fernel, Fernside, Farnsworth, etc. Also, in names of places as Ferney, Ferndale, Fernwood, and others. Although the bracken is coarse and common, it makes a desirable background for rockeries, or other fern masses. The young ferns should be transplanted in early spring with as much of the long, running rootstock as possible.
Var. pseudocaudàta has longer, narrower and more distant pinnules, and is a common southern form.
Var. pseudocaudata
2. MAIDENHAIR. Adiantum
Ferns with much divided leaves and short, marginal sori borne at the ends of free-forking veins, on the under side of the reflexed and altered portion of the pinnules, which serves as an indusium. Stipes and branches of the leaves very slender and polished.
(Greek, unwetted, because drops of water roll off without wetting the leaves.)
(1) COMMON MAIDENHAIR. Adiantum pedatum
A graceful fern of shady glen and rocky woodland, nine to eighteen inches high, the black, shining stalks forked at the top into two equal, recurved branches, the pinnæ all springing from the upper side. Pinnules triangular-oblong, bearing short sori on their inwardly reflexed margins which form the indusium.
[Illustration: A Spray of Maidenhair]
[Illustration: Fruiting Pinnæ of Maidenhair]
The maidenhair has a superficial resemblance to the meadow rue, which also sheds water, but it may be known at once by its black, shining stalks with their divisions all borne on one side. It is indeed a most delicate fern, known and admired by every one. The term maidenhair may have been suggested by the black, wiry roots growing from the slender rootstock, or by the dark, polished stems, or, as Clute explains it, "because the black roots, like hair, were supposed, according to the 'doctrine of signatures' to be good for falling hair, and the plant was actually used in the 'syrup of capillaire'[A] (Am. Botanist, November, 1921). While the maidenhair is not very common, it is widely distributed, being found throughout our section, westward to California, and northward to the British Provinces.
"Though the maidenhair has a wide range, and grows abundantly in many localities, it possesses a quality of aloofness which adds to its charm. Its chosen haunts are dim, moist hollows in the woods, or shaded hillsides sloping to the river. In such retreats you find the feathery fronds tremulous on their glistening stalks, and in their neighborhood you find, also, the very spirit of the woods."
MRS. PARSONS.
[Footnote A: It may be stated that capillaire syrup besides the use here indicated was highly esteemed as a pectoral for the relief of difficult breathing.]
[Illustration: Common Maidenhair. Adiantum pedatum (Reading, Mass., Kingman)]
[Illustration: Alpine Maidenhair. Adiantum pedatum, Var. aleuticum (Fernald and Collins, Gaspé County, Quebec, 1906) (From the Gray Herbarium)]
The fern is not hard to cultivate if allowed sufficient moisture and shade. Along with the ostrich fern it makes a most excellent combination in a fern border.
Var. ALEUTICUM, or Alpine Maidenhair. A beautiful northern form especially abundant on the high tableland of the Gaspé Peninsula, Quebec, where it is said to cover hundreds of acres. In the east it is often dwarfed--six to ten inches high, growing in tufts with stout rootstocks, having the pinnules finely toothed instead of rounded and the indusia often lunate, rarely twice as long as broad. (Fernald in Rhodora, November, 1905.) Also found in northern Vermont, and to the northwestward.
(2) THE VENUS-HAIR FERN. Adiantum Capíllus-Veneris
Fronds with a continuous main rachis, ovate-lanceolate, twice pinnate below. Pinnules, fan-shaped on slender, black stalks, long, deeply and irregularly incised. Veins extending from the base of the pinnules like the ribs of a fan.
[Illustration: Venus Hair Fern. Adiantum Capillus-Veneris]
While our common maidenhair is a northern fern, the Venus-hair Fern is confined to the southern states. It is rarely found as far north as Virginia, where it meets, but scarcely overlaps its sister fern. The medicinal properties of Adiantum pedatum were earlier ascribed to the more southern species, which is common in Great Britain, but, like many another old remedy, "the syrup of capillaire" is long since defunct.
[3. CLIFF BRAKES. Pellàea]
Sporangia borne on the upper part of the free veins inside the margins, in dot-like masses, but may run together, as in the continuous fruiting line of the bracken. Indusium formed of the reflexed margins of the fertile segments which are more or less membranous. (Pellæa, from the Greek pellos, meaning dusky, in allusion to the dark stipes.)
(1) PURPLE CLIFF BRAKE. Pellæa atropurpùrea
Stipes dark purple or reddish-brown, polished and decidedly hairy and harsh to the touch, at least on one side. Fronds coriaceous, pale, simply pinnate, or bipinnate below; the divisions broadly linear or oblong, or the sterile sometimes oval, chiefly entire, somewhat heart-shaped, or else truncate at the stalked base. Veins about twice forked. Basal scales extending into long, slender tips, colorless or yellow.
[Illustration: Purple Cliff Brake. Pellæa atropurpurea]
Another name is "the winter brake," as its fronds remain green throughout the winter, especially in its more southern ranges. It grows on rocky ledges with a preference for limestone, and often in full sun. In large and mature fronds its pinnæ are apt to be extremely irregular. While its stipes are purplish, its leaves are bluish-green, and its scales light-brown or yellow. Strange to say, this brake of the cliffs thrives in cultivation. Woolson says of it, "This fern is interesting and valuable. It is not only beautiful in design, but unique in color, a dark blue-green emphasizing all the varying tints about it--a first-class fern for indoor winter cultivation. It is a rapid grower, flourishing but a few feet from coal fire or radiator, in a north or south window. It quickly forgives neglect, and if allowed to dry up out of doors or indoors, recovers in due time when put in a moist atmosphere. It makes but one imperative demand, and that is the privilege of standing still. Overzealous culturists usually like to turn things around, but revolving cliffs are not in the natural order of things. The slender black stipes are very susceptible to changes of light and warped and twisted fronds result."
Dry, calcareous rocks, southern New England and westward. Rare. Var. cristata has forked pinnæ somewhat crowded toward the summit of the frond. Missouri.
(2) SMOOTH CLIFF BRAKE
Pellàea glabella. Pellàea atropurpùrea, var. Bushii
Naked with a few, scattered, spreading hairs, smooth surface and dark polished stipes. Rhizome short with membranous, orange or brown scales having a few bluntish teeth on each edge. Pinnæ sub-opposite, divergent, narrowly oblong, obtuse; base truncate, cordate or clasping, occasionally auricled; lower pinnæ often with orbicular or cordate pinnules. Sterile pinnæ broader, bluish or greenish glaucous above, often crowded to overlapping. The smooth cliff brake has a decidedly northern range, growing from northern Vermont to Missouri, and northwestward, but found rarely, if at all, in southern New England.
[Illustration: Dense Cliff Brake. Cryptogramma densa (From Waters's "Ferns," Henry Holt & Co.)]
(3) DENSE CLIFF BRAKE
Cryptográmma densa. Pellaèa densa
Modern botanists are inclined to place the dense cliff brake and the slender cliff brake under the genus Cryptográmma, which is so nearly like Pellaea that one hesitates to choose between them. The word Cryptográmma means in Greek a hidden line, alluding to the line of sporangia hidden beneath the reflexed margin.
The dense cliff brake may be described as follows:
Stipes three to nine inches tall, blades one to three inches, triangular-ovate, pinnate at the summit, and tripinnate below. Segments linear, sharp-pointed, mostly fertile, having the margins entire and recurved, giving the sori the appearance of half-open pods. Sterile fronds sharply serrate. Stipes in dense tufts ("densa") slender, wiry, light-brown.
This rare little fern is a northern species and springs from tiny crevices in rocks, preferring limestone. Like many other rock-loving species, it produces spores in abundance, having no other effective means of spreading, and its fertile fronds are much more numerous than the sterile ones, and begin to fruit when very small. Gaspé and Mt. Albert in the Province of Quebec, Grey County, Ontario, and in the far west.
(4) SLENDER CLIFF BRAKE
Cryptográmma Stellèri. Pellaèa grácilis
Fronds (including stipes) three to six inches long, thin and slender with few pinnæ. The lower pinnæ pinnately parted into three to five divisions, those of the fertile fronds oblong or linear-oblong; those of the sterile, obovate or ovate, crenulate, decurrent at the base. Confined to limestone rocks. Quebec and New Brunswick, to Vermont, Connecticut, Pennsylvania, and to the northwest.
[Illustration: Slender Cliff Brake. Cryptogramma Stelleri]
We have collected this dainty and attractive little fern on the limestone cliffs of Mt. Horr, near Willoughby Lake, Vt. It grew in a rocky grotto whose sides were kept moist by dripping water. How we liked to linger near its charming abode high on the cliff! And we liked also to speak of it by its pleasing, simple name, "Pellæa gracilis," now changed for scientific reasons, but we still like the old name better.
[(5) THE ROCK BRAKE. PARSLEY FERN]
Cryptográmma acrostichòides
Sterile and fertile fronds very dissimilar; segments of the fertile, linear and pod-like; of the sterile, ovate-oblong, obtuse, and toothed. The plants spring from crevices of rocks and are from six to eight inches high. Stipes of the fertile fronds are about twice as long as the sterile, making two tiers of fronds.
[Illustration: Parsley Fern or Rock Brake. Cryptogramma acrostichoides (California and Oregon) (Herbarium of Geo. E. Davenport)]
The parsley fern is the typical species of the genus Cryptográmma. The indusium is formed of the altered margin of the pinnule, at first reflexed to the midrib, giving it a pod-like appearance, but at length opening out flat and exposing the sporangia. Clute, speaking of this fern as "the rock brake," calls it a border species, as its home is in the far north--Arctic America to Lake Huron, Lake Superior, Colorado and California.
[4. LIP FERNS. Cheilánthes]
Mostly small southern ferns growing on rocks, pubescent or tomentose with much divided leaves. Sori at the end of the veins at first small and roundish, but afterwards more or less confluent. The indusium whitish and sometimes herbaceous, formed of the reflexed margin of the lobes or of the whole pinnule. Veins free, but often obscure. Most of the ferns of this genus grow in dry, exposed situations, where rain is sometimes absent for weeks and months. For this reason they protect themselves by a covering of hairs, scales or wool, which hinders the evaporation of water from the plant by holding a layer of more or less saturated air near the surface of the frond. (In Greek the word means lip flower, alluding to the lip-like indusia.)
(1) ALABAMA LIP FERN. Cheilánthes alabaménsis
Fronds smooth, two to ten inches long, lanceolate, bipinnate. Pinnæ numerous, oblong-lanceolate, the lower usually smaller than those above. Pinnules triangular-oblong, mostly acute, often auricular or lobed at the base. Indusia pale, membranous and continuous except between the lobes. Stipes black, slender and tomentose at the base.
[Illustration: Alabama Lip Fern. Cheilanthes alabamensis (From Waters's "Ferns," Henry Holt & Co.)]
This species of lip fern may be distinguished from all the others within our limits by its smooth pinnæ. On rocks--mountains of Virginia to Kentucky, and Alabama, and westward to Arizona.
(2) HAIRY LIP FERN. Cheilánthes lanòsa, C. véstita
[Illustration: Hairy Lip Fern]
Fronds twice pinnate, lanceolate with oblong, pinnátifid pinnules; seven to fifteen inches tall, slender and rough with rusty, jointed hairs. Pinnæ triangular-ovate, usually distant, the ends of the rounded lobes reflexed and forming separate involucres which are pushed back by the ripening sporangia.
This species like the other lip ferns is fond of rocks, springing from clefts and ledges. While hairy it is much less tomentose than the two following species. Unlike most of the rock-loving ferns this species is not partial to limestone, but grows on other rocks as well. It has been found as far north as New Haven, Conn., also near New York, and in New Jersey, Georgia, and westward to Wyoming and southward.
(3) WOOLLY LIP FERN. Cheilánthes tomentòsa
Fronds eight to eighteen inches long, lanceolate-oblong, tripinnate. Pinnæ and pinnules ovate-oblong, densely woolly especially beneath, with slender, whitish, obscurely jointed hairs. Of the ultimate segments the terminal one is twice as long as the others. Pinnules distant, the reflexed, narrow margin forming a continuous, membranous indusium. Stipe stout, dark brown, densely woolly.
By donning its thick coat of wool this species is prepared to grow in the most exposed situations of the arid southwest. It is said to be the "rarest, tallest and handsomest of the lip ferns."
Mountains of Virginia and Kentucky to Georgia, and west to Missouri, Texas and Arizona.
(4) SLENDER LIP FERN
Cheilánthes Féei, C. lanuginòsa
Stipes densely tufted, slender, at first hairy, dark brown, shining. Fronds three to eight inches long, ovate-lanceolate, with thickish, distinctly articulated hairs, twice or thrice pinnate. Pinnæ ovate, the lowest deltoid. Pinnules divided into minute, densely crowded segments, the herbaceous margin recurved and forming an almost continuous indusium.
[Illustration: Slender Lip Fern]
The slender lip fern, known also as Fée's fern, is much the smallest of the lip ferns, averaging, Clute tells us, "but two inches high." This is only one-third as tall as the woolly lip fern and need not be mistaken for it. The fronds form tangled mats difficult to unravel. It grows on dry rocks and cliffs--Illinois and Minnesota to British Columbia, and south to Texas, New Mexico and Arizona.
[Illustration: Pinnæ of Slender Lip Fern. Cheilanthes Féei (From Waters's "Ferns," Henry Holt & Co.)]
[5. CLOAK FERN. Notholàena]
Small ferns with fruit-dots borne beneath the revolute margin of the pinnules, at first roundish, but soon confluent into a narrow band without indusium. Veins free. Fronds one to several times pinnate, the lower surface hairy, or tomentose or powdery. Includes about forty species, mostly American, but only one within our limits. (Greek name means spurious cloak, alluding to the rudimentary or counterfeit indusium.)
(1) POWDERY CLOAK FERN. Notholàena dealbàta
Fronds two to six inches long, triangular-ovate, acute, broadest at the base, tripinnate. Stalks tufted, wiry, shining, dark brown. Upper surface of the very small segments green, smooth, the lower densely coated with a pure, white powder; hence, the specific name dealbata, which means whitened. Sori brown at length; veins free.
There are several species of cloak ferns, but only one within our limits. The dry, white powder which covers them doubtless is designed to protect them from too rapid evaporation of moisture, as they all inhabit dry and sunny places. This delicate rock-loving fern is found in the clefts of dry limestone rocks in Missouri, Kansas, Colorado, and southwestward.
[Illustration: Powdery Cloak Fern. Notholaena dealbata (Kansas) (G.E. Davenport)]
[THE CHAIN FERNS. Woodwardia]
Large and somewhat coarse ferns of swampy woods with pinnate or nearly two-pinnate fronds, and oblong or linear fruit-dots, arranged in one or more chain-like rows, parallel to and near the midribs. Indusium fixed by its outer margin to a veinlet and opening on the inner side. In our section there are two species. (Named for Thomas J. Woodward, an English botanist.)
(1) THE COMMON CHAIN FERN. Woodwardia virgínica
Sterile and fertile fronds similar in outline, two to four feet high, once pinnate, the pinnæ deeply incised with oblong segments. Fruit-dots oblong in chain-like rows along the midrib both of the pinnæ and the lobes, confluent when ripe. Veins forming narrow rows of net-like spaces (areoles) beneath the fruit-dots, thence free to the margin. The spores ripen in July.
[Illustration: The Common Chain Fern. Woodwardia virginica]
The sterile fronds resemble those of the cinnamon fern, but the latter grow in crowns, with a single frond in the center, while the fronds of the chain fern rise singly from the creeping rootstock, which sends them up at intervals all summer. The sori are borne on the backs of fertile fronds. There are usually more sterile than fertile blades, especially in dense shade. We have waded repeatedly through a miry swamp in Melrose, Mass., where the wild calla flourishes along with the blueberry and other swamp bushes, and have found the chain fern in several shaded spots, but every frond was sterile. It is said that when exposed to the sun it always faces the south. Swamps, Maine to Florida, especially along the Atlantic Coast, and often in company with the narrow-leaved species.
[Illustration: Net-Veined Chain Fern. Woodwardia areolata (Stratford, Conn.)]
(2) NET-VEINED CHAIN FERN
NARROW-LEAVED CHAIN FERN
Woodwardia areolàta. W. angustifòlia
Root stocks creeping and chaffy. Sterile and fertile fronds unlike; sterile ones nine to twelve inches tall, deltoid-ovate. Broadest at the base, with lanceolate, serrulate divisions united by a broad wing. Veins areolate; fertile fronds taller, twelve to twenty inches high with narrowly linear divisions, the areoles and fruit-dots in a single row each side of the secondary midrib, the latter sunk in the tissues.
This species is less common than the Virginia fern, but they often grow near each other. We have collected both in the Blue Hill reservation near Boston, and both have been found in Hingham, Medford, and Reading, and doubtless in other towns along the coast. Mrs. Parsons speaks of finding them in the flat, sandy country near Buzzard's Bay. The net-veined species has some resemblance to the sensitive fern, but in the latter the spore cases are shut up in small pods formed by the contracting and rolling up of the lobes, whereas the chain fern bears its sori on the under side of long, narrow pinnæ. Besides, the sterile fronds of the latter have serrulate segments. As in the sensitive fern there are many curious gradations between the fertile and sterile fronds, both in shape and fruitfulness. Waters calls them the "obtusilobàta form."
[Illustration: The Spleenworts 1. Narrow-leaved 2. Ebony 3. Rue 4. Scott's 5. Maidenhair 6. Green 7. Mountain]
[THE SPLEENWORTS]
[A. THE ROCK SPLEENWORTS. Asplènium]
Small, evergreen ferns. Fruit-dots oblong or linear, oblique, separate when young. Indusium straight or rarely curved, fixed lengthwise on the upper side of a fertile veinlet, opening toward the midrib. Veins free. Scales of rhizome and stipes narrow, of firm texture and with thick-walled cells.
(1) PINNÀTIFID SPLEENWORT. Asplenium pinnatífídum
Fronds four to six inches long, lanceolate, pinnátifid or pinnate near the base, tapering above into a slender prolongation. Lobes roundish-ovate, or the lower pair acuminate. Fruit-dots irregular, numerous. Stipes tufted, two to four inches long, brownish beneath, green above.
Although this fern, like all the small spleenworts, is heavily fruited, it is extremely rare. It is found as far north as Sharon, Conn., thence southward to Georgia, to Arkansas and Missouri. On cliffs and rocks. Resembles the walking fern, and its tip sometimes takes root.
(2) SCOTT'S SPLEENWORT. Asplenium ebenòides
Fronds four to ten inches long, broadly lanceolate, pinnátifid or pinnate below, tapering to a prolonged and slender apex. Divisions lanceolate from a broad base. Fruit-dots straight or slightly curved. Stipe and rachis brown.
[Illustration: Pinnatifid Spleenwort. Asplenium pinnatifidum a, Small Plants from Harper's Ferry; b, Sori on Young Fronds (From Waters's "Ferns," Henry Holt & Co.)]
[Illustration: Scott's Spleenwort. Asplenium ebenoides a, from Virginia; b, from Alabama; c, from Maryland (From Waters's "Ferns," Henry Holt & Co.)]
Resembles the last, and like that has been known to root at the tip. It is a hybrid between the walking fern and the ebony spleenwort, as proved by Miss Margaret Slosson, and may be looked for in the immediate vicinity of its parents. It was discovered by R.R. Scott, in 1862, at Manayunk, Pa., a suburb of Philadelphia, and described by him in the Gardener's Monthly of September, 1865. Vermont to Alabama, Missouri, and southward. Rare, but said to be plentiful in a deep ravine near Havana, Ala.
[Illustration: Green Spleenwort. Asplenium víride]
(3) GREEN SPLEENWORT. Asplenium víride
Fronds two to ten inches long, linear, pinnate, pale green. Pinnæ roundish-ovate, crenate, with indistinct and forking midveins. Stalks tufted, short, brownish below, green above. Rachis green.
Discovered at Smuggler's Notch, Mt. Mansfield, Vt., by C.G. Pringle in 1876. Found sparingly at Willoughby Lake, high on the cliffs of Mt. Horr. This rare and delicate little plant bears a rather close resemblance to the maidenhair spleenwort, which, however, has dark stipes instead of green.
Northern New England, west and northwest on shaded limestone rocks.
[Illustration: Maidenhair Spleenwort. Asplenium Trichomanes]
(4) MAIDENHAIR SPLEENWORT. Asplenium Trichómanes
Stipes densely tufted, purple-brown, shining. Fronds three to eight inches long, linear, dark green, rather rigid. Pinnæ roundish-oblong or oval, entire or finely crenate, attached at the base by a narrow point. Midveins forking and evanescent.
Not very common, but distributed almost throughout North America. May be looked for wherever there are ledges, as it does not require limestone. July.
[Illustration: Maidenhair Spleenwort. Asplenium Trichomanes (From Woolson's "Ferns," Doubleday, Page & Co.)]