2. NOTHOLae'NA, R. Brown. CLOAK-FERN.

Fruit-dots roundish or oblong, placed near the ends of the veins, soon more or less confluent into an irregular marginal band, with no proper involucre. Veins always free. Fronds of small size, 1--4-pinnate, the lower surface almost always either hairy, tomentose, chaffy, or covered with a fine waxy white or yellow powder. (Name from ?????, _spurious_, and ?a??a, _a cloak_, the woolly coating of the original species forming a spurious covering to the sporangia.)

1. N. dealbata, Kunze. Fronds triangular-ovate, 1--3' long, 3--4-pinnate; rhachis and branches straight, black and shining; ultimate pinnules scarcely a line long, white and powdery on the lower surface.--Clefts of calcareous rocks, Mo., Kan., and southwestward.

July--Aug.

3. ADIaNTUM, L. MAIDENHAIR. (Pl. 17.)

Fruit-dots marginal, short, borne on the under side of a transversely oblong, crescent-shaped or roundish, more or less altered margin or summit of a lobe or tooth of the frond reflexed to form an indusium; the sporangia attached to the approximated tips of the free forking veins.--Main rib (costa) of the pinnules none (in our species), or at the lower margin. Stipes black and polished. (The ancient name, from a privative and d?a???, meaning _unwetted_, the smooth foliage repelling rain-drops.)

1. A. pedatum, L. (Pl. 17, fig. 1--3.) _Frond forked at the summit of the upright slender stalk_ (9--15' high), the recurved branches bearing on one side several slender spreading pinnate divisions; pinnules numerous, short-stalked and obliquely triangular-oblong, entire on the lower margin, from which the veins all proceed, and cleft and fruit-bearing on the other.--Rich, moist woods. July.--A delicate and most graceful Fern.

2. A. Capillus-Veneris, L. _Fronds with a continuous main rhachis, ovate-lanceolate_, 9--18' long, often pendent, 2--3-pinnate at the base, the upper third or half simply pinnate; pinnules wedge-obovate or rhomboid, 6--12" long, deeply and irregularly incised; veinlets flabellately forking from the base; involucres lunulate or transversely oblong.--Moist rocky places, Va. to Mo., and southward. (Eu.)

4. PTeRIS, L. BRAKE or BRACKEN. (Pl. 17.)

Sporangia in a continuous slender line of fructification, occupying the entire margin of the fertile frond, and covered by its reflexed narrow edge which forms a continuous membranaceous indusium, attached to an uninterrupted transverse vein-like receptacle connecting the tips of the forked free veins.--Fronds 1--3-pinnate or decompound. (The ancient Greek name of Ferns, from pte???, _a wing_, on account of the prevalent pinnate or feathery fronds.)

1. P. aquilna, L. (COMMON BRAKE.) Frond dull green (2--3 wide), ternate at the summit of an erect stout stalk (1--2 high), the widely spreading branches twice pinnate; pinnules oblong-lanceolate; the upper undivided; the lower more or less pinnatifid, with oblong obtuse lobes, margined all round with the indusium, which is really double in this species.--Var. CAUDaTA, with the lobes very narrow and revolute, the terminal ones much elongated, is a southern form, which extends in a modified condition as far north as New Jersey.--Thickets and hillsides, common. Aug. (Eu.)

5. CHEILaNTHES, Swartz. LIP-FERN. (Pl. 17.)

Sporangia borne on the thickened ends of free veinlets, forming small and roundish distinct or nearly contiguous marginal fruit-dots, covered by a mostly whitish and membranaceous, sometimes herbaceous, common indusium, formed of the reflexed margin of separate lobes or of the whole pinnule.--Low, mostly with 2--3-pinnate and hairy or chaffy, rarely smooth fronds, the sterile and fertile nearly alike, the divisions with the princ.i.p.al vein central. Some species with continuous indusium connect this genus very closely with the next. (Name composed of ?e????, _a lip_, and ?????, _flower_, from the shape of the indusium.)

[*] _Fronds smooth, or at most hairy._

1. C. Alabamensis, Kunze. _Fronds smooth_, chartaceous (2--8' long), ovate-lanceolate, bipinnate; pinnae numerous, oblong-lanceolate; pinnules triangular-oblong, rather acute, often auriculate or lobed; _indusium continuous, rather broad, pale, and of firm consistence_.--On rocks, mountains of Va. to Ky., and southward.

2. C. vestta, Swartz. (Pl. 17, fig. 1, 2.) Fronds (6--15' high), lanceolate-oblong, hirsute, as are the brown and shining stipes, with _straightish prominently articulated rusty hairs_, twice pinnate; pinnae rather distant, triangular-ovate; pinnules oblong, crowded (2--4"

long), more or less incised, _the ends of the roundish or oblong lobes reflexed and forming separate herbaceous involucres_, which are pushed back by the ripened sporangia.--Clefts of rocks, Manhattan Island (_W. W. Denslow_) and N. J. to Ill., and southward.

[*][*] _Fronds woolly or tomentose._

3. C. tomentsa, Link. Fronds (12--20' high) lanceolate-oblong, densely tomentose with _slender and entangled whitish obscurely articulated hairs_, thrice pinnate; primary and secondary pinnae oblong or ovate-oblong; _pinnules distinct_, minute (--1" long), roundish-obovate, sessile or adnate-decurrent, the upper surface less woolly, _the reflexed narrow margin forming a continuous somewhat membranaceous indusium_.--Mountains of Va. and Ky.; thence west and southward.--Stipe and rhachis rather stout, brown, covered with narrow chaffy scales and whitish hairs.

4. C. lanuginsa, Nutt. Stipes slender, at first hairy, black or brown, shining; fronds (3--6' high) ovate-lanceolate, woolly with _soft whitish distinctly articulated flattened hairs_, becoming smoother above, twice or thrice pinnate; pinnae (5--6" long) ovate, the lowest distant, the others contiguous; _pinnules crenately pinnatifid_, or mostly divided into minute and roundish densely crowded segments (--1" long), _the herbaceous margin recurved forming an almost continuous indusium_.--In dense tufts, on dry rocks and cliffs, Ill. to Minn., thence west and southward.

6. PELLae'A, Link. CLIFF-BRAKE. (Pl. 16.)

Sporangia in roundish or elongated cl.u.s.ters on the upper part of the free veins, distinct, or confluent laterally so as to imitate the marginal continuous line of fructification of Pteris, commonly covered by a broad membranaceous and continuous (rarely interrupted) general indusium, which consists of the reflexed and altered margin of the fertile pinnule or division. Small ferns, with 1--3-pinnate fronds, the fertile ones with narrower divisions than the sterile, but otherwise similar. Stipes generally dark-colored, smooth and shining. (Name from pe????, _dusky_, alluding to the stipe.)

1. P. gracilis, Hook. (Pl. 16.) Fronds smooth (3--6' high), _delicately membranaceous and slender_, of few pinnae, the lower ones once or twice pinnately parted into 3--5 decurrent divisions, those of the fertile frond oblong or linear-oblong, entire or sparingly incised; of the sterile ovate or obovate, crenate or incised; veins of the fertile fronds mostly only once forked.--Shaded calcareous rocks, Ma.s.s. to Minn., and northward; rare. July.--Rootstock very slender, creeping; stipes polished, brownish, darker and sparingly chaffy at base.

2. P. atropurpurea, Link. Smooth, except some bristly-chaffy hairs on the midribs and especially on the _dark purple and polished stalk_ and rhachis, 6--15' high; _frond coriaceous_, pale, once or below twice pinnate; 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.--Dry calcareous rocks; not common, but of wide range. July.--Rootstock short and stout; stipes cl.u.s.tered.

7. CRYPTOGRaMME, R. Brown. ROCK-BRAKE.

Fruit-dots roundish or elongated and extending far down on the free forking veins. True involucre or indusium none, the herbaceous margins of the fertile segments at first reflexed and meeting at the midrib, at length opening out flat and exposing the confluent sporangia.--Low ferns, with smooth, 2--3-pinnate fronds, the fertile ones taller than the sterile, and with much narrower divisions. (Name from ???pt??, _hidden_, and ??a?, _a line_, alluding to the lines of sporangia at first concealed by the reflexed margin.)

1. C. acrostichodes, R. Brown. Stipes densely tufted, straw-colored; fronds 2--3-pinnate (6--10' high); fertile segments stalked, linear or linear-oblong (3--5" long), the sporangia in lines extending down the veins almost to the midrib, confluent when ripe and covering the under surface of the now fully opened segments; sterile fronds on much shorter stipes, with ovate or obovate decurrent and crenately toothed or incised segments. (Allosorus acrostichoides, _Sprengel_.)--On rocks, from L. Superior westward and northward.--Very near C. crispa of Eu.

8. WOODWaRDIA, Smith. CHAIN-FERN. (Pl. 17.)

Fruit-dots oblong or linear, arranged in one or more chain-like rows on transverse anastomosing veinlets parallel and near to the midrib.

Indusium fixed by its outer margin to the fruitful veinlet, free and opening on the side next the midrib. Veins more or less reticulated, free toward the margin of the frond.--Large ferns, with pinnatifid or pinnate fronds. (Named for _Thomas J. Woodward_, an English botanist.)

-- 1. ANCHiSTEA. _Sterile and fertile fronds alike; veins forming only one row of meshes (areoles)._

1. W. Virginica, Smith. (Pl. 17, fig. 4, 5.) Fronds (2--3 high) pinnate, with numerous lanceolate pinnatifid pinnae; segments oblong; veins forming a row of narrow areoles along the midrib both of the pinnae and of the lobes, the outer veinlets free; fruit-dots oblong, one to each areole, confluent when ripe.--Wet swamps, Maine to Ark., and southward. Rootstocks creeping, often 6--8 long! July.

-- 2. LORINSeRIA. _Sterile and fertile fronds unlike; veins of the sterile fronds forming many rows of meshes._

2. W. angustiflia, Smith. (Pl. 17, fig. 1--3.) Fronds pinnatifid; sterile ones (12--18' high) with lanceolate serrulate divisions united by a broad wing; fertile fronds taller, with narrowly linear almost disconnected divisions, the areoles and fruit-dots (4--5" long) in a single row each side of the secondary midribs; rootstocks creeping.--Wet woods, New Eng., near the coast, to Ark., and southward; rare. Aug., Sept.

9. ASPLeNIUM, L. SPLEENWORT. (Pl. 18.)

Fruit-dots oblong or linear, oblique, separate; the straight, or rarely curved, indusium fixed lengthwise by one edge to the upper (inner) side of the fertile vein;--in some species a part of the fruit-dots are double, the fertile vein bearing two indusia placed back to back. Veins free in all our species. (Name from a- privative and sp???, _the spleen_, for supposed remedial properties.)

-- 1. ASPLENIUM proper. _Indusium straight or slightly curved, attached to the upper side of the vein, rarely double._

[*] _Small evergreen ferns; fronds pinnatifid, or pinnate only near the base._

1. A. pinnatifidum, Nutt. _Fronds_ (3--6' long) lanceolate, _pinnatifid, or pinnate below, tapering above into a slender prolongation_, "the apex sometimes rooting"; _lobes roundish-ovate, obtuse, or the lowest pair long-ac.u.minate_; fruit-dots irregular, those next the midrib often double, even the slender prolongation fertile.--On cliffs and rocks, Penn. to Mo., and southward; very rare. July.--Resembles the Walking-Leaf (Camptosorus), but the veins are free. _Stipes brownish, becoming green above, and so pa.s.sing into the broad pale green midrib._

2. A. ebenodes, R. R. Scott. _Fronds_ (4--9' long) broadly lanceolate _pinnatifid, below pinnate, the apex prolonged and slender; divisions lanceolate from a broad base, the lower ones shorter_, often proliferous, as is the apex of the frond; fruit-dots much as in the last; _stipes black and polished, as is the lower part of the midrib, especially beneath_.--Limestone cliffs, Conn. and Penn., and southward; very rare, usually growing with Camptosorus and Asplenium ebeneum, of which _Rev. M. G. Berkeley_ considered it a probable hybrid.

[*][*] _Small evergreen ferns; the narrow fronds simply pinnate with numerous pinnae._

[+] _Pinnae not auricled._

3. A. viride, Hudson. _Fronds_ (2--5' long) tufted, _linear in outline, pale green, softly herbaceous; pinnae roundish-ovate or ovate-rhomboid_, short-stalked, crenately toothed (2--4" long), the midvein indistinct and forking; _the slender stipe brownish and pa.s.sing into a green herbaceous rhachis_.--Shaded cliffs; northern New Eng., west and northward; rare. (Eu.)

4. A. Trichomanes, L. _Fronds_ (3--8' long) in dense spreading tufts, _linear in outline, dark green and more rigid; pinnae roundish-oblong or oval_ (3--4" long), entire or crenulate, rarely incised, unequal-sided, obliquely wedge-truncate at base, attached by a narrow point, the midvein forking and evanescent; _the thread-like stipe and rhachis purple-brown and shining_.--Shaded cliffs; common. July. (Eu.)

[+][+] _Pinnae more or less auricled._

5. A. parvulum, Mart. & Gal. Fronds upright (4--10' high), narrowly linear-oblanceolate; _pinnae_ (2--6" long) _rigid and thickish, mostly opposite_, nearly sessile, somewhat deflexed, oblong, obtuse, _entire or crenulate_, auricled on the upper or both sides; sori rather few, as near the margin as the continuous midvein; stipe and rhachis black and shining.--Mountains of Va. to Mo., and southward.--Nearly intermediate between the last and the next.

6. A. ebeneum, Ait. Fronds upright (9--18' high), linear-oblanceolate in outline, fertile ones much the taller; _pinnae_ (6--18" long) _firmly membranaceous, mostly alternate_, sessile, spreading, oblong or oblong-linear, _finely serrate or even incised_, the base auricled on the upper or both sides; sori many, nearer the elongated midvein than the margin; stipe and rhachis blackish-purple and shining.--Rocky, open woods; rather common.

[*][*][*] _Small evergreen ferns; the broader fronds 1--3-pinnate; pinnae incised._