# An Illustrated Flora of the Northern United States, Canada and the British Possessions/Polypodiaceae

Family 5.   Polypodiàceae   R. Br.   Prodr. Fl. Nov. Holl. 1: 145.   1810.
Fern Family.
Leafy plants of various habit, the rootstocks horizontal and often elongate, or shorter and erect, the leaf-blades simple, once or several times pinnate or pinnatifid, or decompound, coiled in vernation.  Sporanges borne on the under surface of the foliaceous leaf-blades, or upon slender or contracted, partially foliose or non-foliose leaves or parts of leaves, or, as in most of our species, in clusters (sori) upon the backs of the leaf-blades; distinctly stalked, provided with an incomplete vertical ring of thickened cells (the annulus), and opening transversely.  Sori either with or without a membranous covering (indusium).  Prothallia green.
About 145 genera and 4500 or more species of very wide geographic distribution.  This family includes by far the greater number of living ferns.
Leaves strongly dimorphous, the fertile ones with divisions greatly contracted, brownish, berry-like or necklace-like. :
| | • | Sterile blades deeply pinnatifid; veins freely anastomosing. | Sterile blades deeply pinnatifid; veins freely anastomosing. | Sterile blades deeply pinnatifid; veins freely anastomosing. | Sterile blades deeply pinnatifid; veins freely anastomosing. | Sterile blades deeply pinnatifid; veins freely anastomosing. | Sterile blades deeply pinnatifid; veins freely anastomosing. | Sterile blades deeply pinnatifid; veins freely anastomosing. | Sterile blades deeply pinnatifid; veins freely anastomosing. | Sterile blades deeply pinnatifid; veins freely anastomosing. | 1. | Onoclea. |
| | • | Sterile blades deeply 2-pinnatifid; veins free. | Sterile blades deeply 2-pinnatifid; veins free. | Sterile blades deeply 2-pinnatifid; veins free. | Sterile blades deeply 2-pinnatifid; veins free. | Sterile blades deeply 2-pinnatifid; veins free. | Sterile blades deeply 2-pinnatifid; veins free. | Sterile blades deeply 2-pinnatifid; veins free. | Sterile blades deeply 2-pinnatifid; veins free. | Sterile blades deeply 2-pinnatifid; veins free. | 2. | Matteuccia. |
| • | Leaves mostly uniform; if dimorphous, the fertile blades flat, the divisions green, not as above. | Leaves mostly uniform; if dimorphous, the fertile blades flat, the divisions green, not as above. | Leaves mostly uniform; if dimorphous, the fertile blades flat, the divisions green, not as above. | Leaves mostly uniform; if dimorphous, the fertile blades flat, the divisions green, not as above. | Leaves mostly uniform; if dimorphous, the fertile blades flat, the divisions green, not as above. | Leaves mostly uniform; if dimorphous, the fertile blades flat, the divisions green, not as above. | Leaves mostly uniform; if dimorphous, the fertile blades flat, the divisions green, not as above. | Leaves mostly uniform; if dimorphous, the fertile blades flat, the divisions green, not as above. | Leaves mostly uniform; if dimorphous, the fertile blades flat, the divisions green, not as above. | Leaves mostly uniform; if dimorphous, the fertile blades flat, the divisions green, not as above. |
| | • | Sori dorsal upon the veins, not marginal. | Sori dorsal upon the veins, not marginal. | Sori dorsal upon the veins, not marginal. | Sori dorsal upon the veins, not marginal. | Sori dorsal upon the veins, not marginal. | Sori dorsal upon the veins, not marginal. | Sori dorsal upon the veins, not marginal. | Sori dorsal upon the veins, not marginal. | Sori dorsal upon the veins, not marginal. |
| | | • | Sori roundish. | Sori roundish. | Sori roundish. | Sori roundish. | Sori roundish. | Sori roundish. | Sori roundish. | Sori roundish. |
| | | | • | Indusium wholly or partially inferior. | Indusium wholly or partially inferior. | Indusium wholly or partially inferior. | Indusium wholly or partially inferior. | Indusium wholly or partially inferior. | Indusium wholly or partially inferior. | Indusium wholly or partially inferior. |
| | | | | • | Indusium wholly inferior, the divisions stellate or spreading. | Indusium wholly inferior, the divisions stellate or spreading. | Indusium wholly inferior, the divisions stellate or spreading. | Indusium wholly inferior, the divisions stellate or spreading. | Indusium wholly inferior, the divisions stellate or spreading. | Indusium wholly inferior, the divisions stellate or spreading. | 3. | Woodsia. |
| | | | | • | Indusium attached by its base at one side of the sorus, hood-shaped, withering. | Indusium attached by its base at one side of the sorus, hood-shaped, withering. | Indusium attached by its base at one side of the sorus, hood-shaped, withering. | Indusium attached by its base at one side of the sorus, hood-shaped, withering. | Indusium attached by its base at one side of the sorus, hood-shaped, withering. | Indusium attached by its base at one side of the sorus, hood-shaped, withering. | 5. | Filix. |
| | | | • | Indusium, if present, superior. | Indusium, if present, superior. | Indusium, if present, superior. | Indusium, if present, superior. | Indusium, if present, superior. | Indusium, if present, superior. | Indusium, if present, superior. |
| | | | | • | Stipes jointed to the rootstock; indusia wanting. | Stipes jointed to the rootstock; indusia wanting. | Stipes jointed to the rootstock; indusia wanting. | Stipes jointed to the rootstock; indusia wanting. | Stipes jointed to the rootstock; indusia wanting. | Stipes jointed to the rootstock; indusia wanting. | 20. | Polypodium. |
| | | | | • | Stipes continuous with the rootstock (not jointed); indusia present in most species. | Stipes continuous with the rootstock (not jointed); indusia present in most species. | Stipes continuous with the rootstock (not jointed); indusia present in most species. | Stipes continuous with the rootstock (not jointed); indusia present in most species. | Stipes continuous with the rootstock (not jointed); indusia present in most species. | Stipes continuous with the rootstock (not jointed); indusia present in most species. |
| | | | | | • | Indusium (present, in our -species) orbicular-peltate, centrally attached. | Indusium (present, in our -species) orbicular-peltate, centrally attached. | Indusium (present, in our -species) orbicular-peltate, centrally attached. | Indusium (present, in our -species) orbicular-peltate, centrally attached. | Indusium (present, in our -species) orbicular-peltate, centrally attached. | 6. | Polystichum. |
| | | | | | • | Indusium, if present, orbicular-reniform, attached at its sinus. | Indusium, if present, orbicular-reniform, attached at its sinus. | Indusium, if present, orbicular-reniform, attached at its sinus. | Indusium, if present, orbicular-reniform, attached at its sinus. | Indusium, if present, orbicular-reniform, attached at its sinus. | 7. | Dryopteris. |
| | | • | Sori oblong to linear. | Sori oblong to linear. | Sori oblong to linear. | Sori oblong to linear. | Sori oblong to linear. | Sori oblong to linear. | Sori oblong to linear. | Sori oblong to linear. |
| | | | • | Sori in chain-like rows parallel to the midrib and rachises. | Sori in chain-like rows parallel to the midrib and rachises. | Sori in chain-like rows parallel to the midrib and rachises. | Sori in chain-like rows parallel to the midrib and rachises. | Sori in chain-like rows parallel to the midrib and rachises. | Sori in chain-like rows parallel to the midrib and rachises. | Sori in chain-like rows parallel to the midrib and rachises. |
| | | | | • | Leaves uniform ; veins free between the sori and margin. | Leaves uniform ; veins free between the sori and margin. | Leaves uniform ; veins free between the sori and margin. | Leaves uniform ; veins free between the sori and margin. | Leaves uniform ; veins free between the sori and margin. | Leaves uniform ; veins free between the sori and margin. | 8. | Anchistea. |
| | | | | • | Leaves dimorphous ; veins of sterile blade freely anastomosing. | Leaves dimorphous ; veins of sterile blade freely anastomosing. | Leaves dimorphous ; veins of sterile blade freely anastomosing. | Leaves dimorphous ; veins of sterile blade freely anastomosing. | Leaves dimorphous ; veins of sterile blade freely anastomosing. | Leaves dimorphous ; veins of sterile blade freely anastomosing. | 9. | Lorinseria. |
| | | | • | Sori oblique to the midribs or irregularly disposed. | Sori oblique to the midribs or irregularly disposed. | Sori oblique to the midribs or irregularly disposed. | Sori oblique to the midribs or irregularly disposed. | Sori oblique to the midribs or irregularly disposed. | Sori oblique to the midribs or irregularly disposed. | Sori oblique to the midribs or irregularly disposed. |
| | | | | • | Veins free; sori all oblique to the midribs. | Veins free; sori all oblique to the midribs. | Veins free; sori all oblique to the midribs. | Veins free; sori all oblique to the midribs. | Veins free; sori all oblique to the midribs. | Veins free; sori all oblique to the midribs. |
| | | | | | • | Sori confluent in pairs; indusia single, contiguous, appearing double. | Sori confluent in pairs; indusia single, contiguous, appearing double. | Sori confluent in pairs; indusia single, contiguous, appearing double. | Sori confluent in pairs; indusia single, contiguous, appearing double. | Sori confluent in pairs; indusia single, contiguous, appearing double. | 10. | Phyllitis. |
| | | | | | • | Sori single on the outer side of veinlet, or crossing it and recurved. | Sori single on the outer side of veinlet, or crossing it and recurved. | Sori single on the outer side of veinlet, or crossing it and recurved. | Sori single on the outer side of veinlet, or crossing it and recurved. | Sori single on the outer side of veinlet, or crossing it and recurved. |
| | | | | | | • | Sori straight or slightly curved ; leaves mostly evergreen. | Sori straight or slightly curved ; leaves mostly evergreen. | Sori straight or slightly curved ; leaves mostly evergreen. | Sori straight or slightly curved ; leaves mostly evergreen. | 12. | Aspleninum. |
| | | | | | | • | Sori usually curved, often crossing the veinlet and recurved; leaves herbaceous. | Sori usually curved, often crossing the veinlet and recurved; leaves herbaceous. | Sori usually curved, often crossing the veinlet and recurved; leaves herbaceous. | Sori usually curved, often crossing the veinlet and recurved; leaves herbaceous. | 13. | Athyrium. |
| | | | | • | Veins freely anastomosing; sori variously disposed. | Veins freely anastomosing; sori variously disposed. | Veins freely anastomosing; sori variously disposed. | Veins freely anastomosing; sori variously disposed. | Veins freely anastomosing; sori variously disposed. | Veins freely anastomosing; sori variously disposed. | 11. | Camptosorus. |
| | • | Sori borne at or very near the margin. | Sori borne at or very near the margin. | Sori borne at or very near the margin. | Sori borne at or very near the margin. | Sori borne at or very near the margin. | Sori borne at or very near the margin. | Sori borne at or very near the margin. | Sori borne at or very near the margin. | Sori borne at or very near the margin. |
| | | • | Sporanges borne within a special cup-shaped indusium. | Sporanges borne within a special cup-shaped indusium. | Sporanges borne within a special cup-shaped indusium. | Sporanges borne within a special cup-shaped indusium. | Sporanges borne within a special cup-shaped indusium. | Sporanges borne within a special cup-shaped indusium. | Sporanges borne within a special cup-shaped indusium. | Sporanges borne within a special cup-shaped indusium. | 4. | Dennstaedtia. |
| | | • | Sporanges not borne within a special cup-shaped indusium. | Sporanges not borne within a special cup-shaped indusium. | Sporanges not borne within a special cup-shaped indusium. | Sporanges not borne within a special cup-shaped indusium. | Sporanges not borne within a special cup-shaped indusium. | Sporanges not borne within a special cup-shaped indusium. | Sporanges not borne within a special cup-shaped indusium. | Sporanges not borne within a special cup-shaped indusium. |
| | | | • | Sori without indusia, somewhat protected by the revolute leaf-margin. | Sori without indusia, somewhat protected by the revolute leaf-margin. | Sori without indusia, somewhat protected by the revolute leaf-margin. | Sori without indusia, somewhat protected by the revolute leaf-margin. | Sori without indusia, somewhat protected by the revolute leaf-margin. | Sori without indusia, somewhat protected by the revolute leaf-margin. | Sori without indusia, somewhat protected by the revolute leaf-margin. | 19. | Notholaena. |
| | | | • | Sori with indusia formed entirely or in part by the revolute or reflexed more or less modified leaf-margins. | Sori with indusia formed entirely or in part by the revolute or reflexed more or less modified leaf-margins. | Sori with indusia formed entirely or in part by the revolute or reflexed more or less modified leaf-margins. | Sori with indusia formed entirely or in part by the revolute or reflexed more or less modified leaf-margins. | Sori with indusia formed entirely or in part by the revolute or reflexed more or less modified leaf-margins. | Sori with indusia formed entirely or in part by the revolute or reflexed more or less modified leaf-margins. | Sori with indusia formed entirely or in part by the revolute or reflexed more or less modified leaf-margins. |
| | | | | • | Sori distinct, borne on the under side of the reflexed lobes. | Sori distinct, borne on the under side of the reflexed lobes. | Sori distinct, borne on the under side of the reflexed lobes. | Sori distinct, borne on the under side of the reflexed lobes. | Sori distinct, borne on the under side of the reflexed lobes. | Sori distinct, borne on the under side of the reflexed lobes. | 14. | Adiantum. |
| | | | | • | Sori wholly or partially confluent. | Sori wholly or partially confluent. | Sori wholly or partially confluent. | Sori wholly or partially confluent. | Sori wholly or partially confluent. | Sori wholly or partially confluent. |
| | | | | | • | Sori borne on a vein-like receptacle connecting the ends of the free veinlets; indusium double. | Sori borne on a vein-like receptacle connecting the ends of the free veinlets; indusium double. | Sori borne on a vein-like receptacle connecting the ends of the free veinlets; indusium double. | Sori borne on a vein-like receptacle connecting the ends of the free veinlets; indusium double. | Sori borne on a vein-like receptacle connecting the ends of the free veinlets; indusium double. | 15. | Pteridium. |
| | | | | | • | Sori borne at or near the ends of the free veinlets; indusia single. | Sori borne at or near the ends of the free veinlets; indusia single. | Sori borne at or near the ends of the free veinlets; indusia single. | Sori borne at or near the ends of the free veinlets; indusia single. | Sori borne at or near the ends of the free veinlets; indusia single. |
| | | | | | | • | Leaves dimorphous. | Leaves dimorphous. | Leaves dimorphous. | Leaves dimorphous. | 16. | Cryptogramma. |
| | | | | | | • | Leaves uniform or nearly so. | Leaves uniform or nearly so. | Leaves uniform or nearly so. | Leaves uniform or nearly so. |
| | | | | | | | • | Sori confluent, forming a wide submarginal band ; segments smooth or nearly so. | Sori confluent, forming a wide submarginal band ; segments smooth or nearly so. | Sori confluent, forming a wide submarginal band ; segments smooth or nearly so. | 17. | Pellaea. |
| | | | | | | | • | Sori distinct or contiguous ; segments usually pubescent, tomentose or scaly. | Sori distinct or contiguous ; segments usually pubescent, tomentose or scaly. | Sori distinct or contiguous ; segments usually pubescent, tomentose or scaly. | 18. | Cheilanthes. |

### 1.0

1.  Onoclèa   L.   Sp. Pl. 1062.   1753.
Coarse lowland ferns with leaves of two very dissimilar sorts borne separately upon a creeping rootstock, the sterile ones foliaceous and suberect, withering with frosts. the fertile ones rigidly erect, with pinnules greatly contractcd into separate hard rounded herry-like divisions, these (until maturity) completely concealing the included sori, finally dehiscent and persistent throughout the winter. Sori roundish, on elevated receotacles. partially covered by delicate hood-shaped indusia fixed at the base of the receptacles.  [Name ancient, not originally applied to this plant.]
A single species, O. sensibilis L.
* 1.  Onoclea sensíbilis  L. Sensitive Fern.   Fig. 21.
* Onoclea sensibilis L. Sp. Pl. 1062.   1753.
* Rootstock rather slender, copiously rooting. Fertile leaves 1°–2½° high. persistent over winter, the fertile portion bipinnate, much contracted, the short pinnules rolled up into closed berry-like bodies and forming a narrow close panicle. Sterile leaves 1°–4½° high, the blades broadly triangular, deeply pinnatifid, the rachis winged; pinnae lanceolate-oblong, entire, undulate, or the lower and sometimes the middle ones sinuate-pinnatifid; veins freely anastomosing, forming a somewhat regular series of narrow elongate areoles next the midvein and numerous smaller areoles between this series and the margin.
* In moist soil, Newfoundland to Saskatchewan, south to Oklahoma and the Gulf states. Ascends to 3000 ft. in Virginia. Various intermediate forms between the sterile and fertile leaves occur. Sensitive to early frosts.  Aug.-Nov.

### 2.0

2.  Matteùccia   Todaro   Giorn. Sci. Nat. Palermo 1: 235.   1866. [Struthiopteris Willd. 1809, not Weiss, 1770.].
Coarse lowland ferns with dissimilar leaves in a close crown upon a stout ascending rootstock. Sterile leaves tall, in a complete circle, the shorter fertile leaves appearing late in the season, borne within, rigidly erect, the pinnae closely contracted into necklace-like or pod-like divisions, these concealing the sori, finally dehiscent. Sori roundish, on elevated cylindrical receptacles, partly covered by delicate fugacious lacerate indusia attached below.  [Named in honor of Carlo Matteucci, an Italian professor of physics.]
Species 3, the following, which is the generic type, and 2 Asiatic species.
* 1.  Matteuccia struthiópteris  (L.) Todaro. Ostrich-fern.   Fig. 22.
* Osmunda Struthiopteris L. Sp. Pl. 1066.   1753.
* Onoclea Struthiopteris Hoffm. Deutsch. Fl. 2: 11.   1795.
* Struthiopteris germanica Willd. Enum. 1071.   1809.
* Matteuccia Struthiopteris Todaro, Giorn. Sci. Nat. Palermo 1: 235.   1866.
* Rootstock stout, ascending, with slender underground stolons. Fertile leaves 1°–1½° high, the pinnae dark brown, slightly crenate, contracted, with closely and widely revolute margins, the included sori crowded and confluent. Sterile leaves 2°–7° high, 6′–15′ broad, broadly oblanceolate or spatulate, abruptly short-acuminate, gradually narrowed below the middle, the lower pinnae greatly reduced; pinnae narrow, deeply pinnatifid, glabrous, the segments oblong, obtuse, entire.
* In moist thickets, especially along streams, Nova Scotia to Virginia, west to British Columbia and Iowa. Ascends to 2000 ft. in Vermont. Also in Europe and Asia.  July-Oct.

### 3.0

3.  Woódsia   R. Br.   Prodr. Fl. Nov. Holl. 1: 158.   1810.
Small or medium-sized ferns, growing in rocky places, the rootstocks in dense tufts. Leaves numerous, the stipes often jointed above the base and separable, the blades 1-2-pinnate or deeply 3-pinnatifid. Sori roundish, borne on the simply-forked free veins. Indusia slight and often evanescent, inferior in attachment, either roundish and soon cleft into irregularly jagged lobes, or deeply stellate, the filiform divisions concealed beneath the sporanges or inflexed and partially covering them.  [Named in honor of Joseph Woods, 1776-1864, an English architect and botanist.]
About 25 species, mainly of temperate or cold regions. Besides the following, another occurs in the southwestern United States. Type species : Polypodium ilvense L.
Indusium small or inconspicuous, the divisions narrow or filiform. :
| | • | Stipes jointed near the base; filiform divisions of the indusium more or less inflexed over the sporanges. | Stipes jointed near the base; filiform divisions of the indusium more or less inflexed over the sporanges. | Stipes jointed near the base; filiform divisions of the indusium more or less inflexed over the sporanges. | Stipes jointed near the base; filiform divisions of the indusium more or less inflexed over the sporanges. | Stipes jointed near the base; filiform divisions of the indusium more or less inflexed over the sporanges. | Stipes jointed near the base; filiform divisions of the indusium more or less inflexed over the sporanges. | Stipes jointed near the base; filiform divisions of the indusium more or less inflexed over the sporanges. | Stipes jointed near the base; filiform divisions of the indusium more or less inflexed over the sporanges. | Stipes jointed near the base; filiform divisions of the indusium more or less inflexed over the sporanges. |
| | | • | Blades with more or less rusty chaff underneath. | Blades with more or less rusty chaff underneath. | Blades with more or less rusty chaff underneath. | Blades with more or less rusty chaff underneath. | Blades with more or less rusty chaff underneath. | Blades with more or less rusty chaff underneath. | Blades with more or less rusty chaff underneath. | Blades with more or less rusty chaff underneath. | 1. | W. ilvensis. |
| | | • | Blades glabrous or nearly so. | Blades glabrous or nearly so. | Blades glabrous or nearly so. | Blades glabrous or nearly so. | Blades glabrous or nearly so. | Blades glabrous or nearly so. | Blades glabrous or nearly so. | Blades glabrous or nearly so. |
| | | | • | Blades oblong-lanceolate; divisions of the indusium numerous. | Blades oblong-lanceolate; divisions of the indusium numerous. | Blades oblong-lanceolate; divisions of the indusium numerous. | Blades oblong-lanceolate; divisions of the indusium numerous. | Blades oblong-lanceolate; divisions of the indusium numerous. | Blades oblong-lanceolate; divisions of the indusium numerous. | Blades oblong-lanceolate; divisions of the indusium numerous. | 2. | W. alpina. |
| | | | • | Blades linear or linear-lanceolate; divisions of the indusium few. | Blades linear or linear-lanceolate; divisions of the indusium few. | Blades linear or linear-lanceolate; divisions of the indusium few. | Blades linear or linear-lanceolate; divisions of the indusium few. | Blades linear or linear-lanceolate; divisions of the indusium few. | Blades linear or linear-lanceolate; divisions of the indusium few. | Blades linear or linear-lanceolate; divisions of the indusium few. | 3. | W. glabella. |
| | • | Stipes not jointed; divisions of the indusium spreading, mostly concealed beneath the sporanges. | Stipes not jointed; divisions of the indusium spreading, mostly concealed beneath the sporanges. | Stipes not jointed; divisions of the indusium spreading, mostly concealed beneath the sporanges. | Stipes not jointed; divisions of the indusium spreading, mostly concealed beneath the sporanges. | Stipes not jointed; divisions of the indusium spreading, mostly concealed beneath the sporanges. | Stipes not jointed; divisions of the indusium spreading, mostly concealed beneath the sporanges. | Stipes not jointed; divisions of the indusium spreading, mostly concealed beneath the sporanges. | Stipes not jointed; divisions of the indusium spreading, mostly concealed beneath the sporanges. | Stipes not jointed; divisions of the indusium spreading, mostly concealed beneath the sporanges. |
| | | • | Puberulent, usually hispidulous; indusium deeply cleft into narrow flaccid segments. | Puberulent, usually hispidulous; indusium deeply cleft into narrow flaccid segments. | Puberulent, usually hispidulous; indusium deeply cleft into narrow flaccid segments. | Puberulent, usually hispidulous; indusium deeply cleft into narrow flaccid segments. | Puberulent, usually hispidulous; indusium deeply cleft into narrow flaccid segments. | Puberulent, usually hispidulous; indusium deeply cleft into narrow flaccid segments. | Puberulent, usually hispidulous; indusium deeply cleft into narrow flaccid segments. | Puberulent, usually hispidulous; indusium deeply cleft into narrow flaccid segments. | 4. | W. scopulina. |
| | | • | Glabrous; indusium divided to the center into a few short whitish turgid beaded hair-like segments. | Glabrous; indusium divided to the center into a few short whitish turgid beaded hair-like segments. | Glabrous; indusium divided to the center into a few short whitish turgid beaded hair-like segments. | Glabrous; indusium divided to the center into a few short whitish turgid beaded hair-like segments. | Glabrous; indusium divided to the center into a few short whitish turgid beaded hair-like segments. | Glabrous; indusium divided to the center into a few short whitish turgid beaded hair-like segments. | Glabrous; indusium divided to the center into a few short whitish turgid beaded hair-like segments. | Glabrous; indusium divided to the center into a few short whitish turgid beaded hair-like segments. | 5. | W. oregana. |
| • | Indusium ample; the divisions broad, early spreading. | Indusium ample; the divisions broad, early spreading. | Indusium ample; the divisions broad, early spreading. | Indusium ample; the divisions broad, early spreading. | Indusium ample; the divisions broad, early spreading. | Indusium ample; the divisions broad, early spreading. | Indusium ample; the divisions broad, early spreading. | Indusium ample; the divisions broad, early spreading. | Indusium ample; the divisions broad, early spreading. | Indusium ample; the divisions broad, early spreading. | 6. | W. obtusa. |

### 3.1

* 1.  Woodsia ilvénsis  (L.) R. Br. Rusty Woodsia   Fig. 23.
* Acrostichum ilvense L. Sp. Pl. 1071.  1753.
* Woodsia ilvensis R. Br. Prodr. Fl. Nov. Holl. 1: 158.  1810.
* Rootstocks short, ascending, growing in masses, the leaves closely caespitose. Stipes short, stoutish, jointed near the base, rusty chaffy with narrow filiform scales; blades lanceolate, 4′–10′ long, pinnate, nearly glabrous above, more or less covered with rusty chaff beneath; pinnae crowded, sessile, pinnately parted, the crowded segments oblong, crenate; sori borne near the margins of the segments, somewhat confluent with age; indusium minute, concealed beneath the sorus, cleft into numerous filiform segments, these inflexed over the sporanges and inconspicuous.
* On exposed rocks, Labrador to Alaska, south to North Carolina, Kentucky and Iowa. Ascends to 5000 ft. in New Hampshire. Also in Greenland. Europe and Asia.  June-Aug.  Ray's Woodsia, Oblong Woodsia.

### 3.2

* 2.  Woodsia alpìna  (Bolton) S. F. Gray. Alpine Woodsia.   Fig. 24.
* Acrostichum alpinum Bolton, Fil. Brit. 76.   1790.
* Acrostichum hyperboreum Liljeb. Kgl. Vetensk. Akad. Nya Handl. 14: 201.   1793.
* Woodsia hyperborea R. Br. Prodr. Fl. Nov. Holl. 1: 158.   1810.
* W. alpina S. F. Gray, Nat. Arr. Brit. Pl. 2: 17.   1821.
* Rootstocks short, ascending, the leaves densely caespitose. Stipes slender, chestnut-colored, shining, somewhat chaffy below, jointed near the base; blades narrowly oblong-lanceolate, 2′–6′ long, 8″–12″ wide, scarcely narrower below the middle, deeply bipinnatifid; pinnae somewhat apart, cordate-ovate or triangular-ovate, pinnately 5-7-lobed, glabrous or very nearly so on both surfaces; sori near the margin, usually distinct; indusium as in the preceding species.
* On moist rocks, Labrador to Alaska, Maine, northern New York and western Ontario. Also in Greenland. Ascends to 4200 ft. in Vermont.  July-Aug.  Called also Northern Woodsia, Flower-cup-fern.

### 3.3

* 3.  Woodsia glabélla  R. Br. Smooth Woodsia.   Fig. 25.
* Woodsia glabella R. Br. App. Franklin's Journ. 754.  1823.
* Rootstocks small, ascending, densely clustered. Stipes very slender, usually stramineous, jointed above the base; blades delicate, linear or narrowly lanceolate, 2′–5′ long, 4″–8″ wide, once pinnate; pinnae deltoid to roundish-ovate, crenately lobed, glabrous, the lower pinnae remote, obtuse, often somewhat smaller than the middle ones; sori few, distinct or with age confluent; indusium minute, with 6-10 hair-like incurved or radiating segments.
* On moist rocks, Labrador to Alaska, south to New Brunswick, northern New England, northern New York and British Columbia. Also in Greenland and arctic and alpine Europe and Asia.  Summer.

### 3.4

* 4.  Woodsia scopulìna  D. C. Eaton. Rocky Mountain Woodsia.   Fig. 26.
* Woodsia scopulina D. C. Eaton, Can. Nat. 2: 90.  1865.
* Woodsia Cathcartiana Robinson, Rhodora 10: 30.  1908.
* Rootstock short, creeping, densely chaffy, the numerous leaves borne close together. Stipes 2′–6′ long, not jointed, bright rusty or chestnut-colored at the base, paler above; blades lanceolate, 6′–12′ long, finely glandular-puberulent and usually hispidulous with jointed whitish hairs; pinnae numerous, oblong-ovate, deeply pinnatifid into 10–16 oblong toothed segments, or fully pinnate, the larger pinnules nearly free and deeply incised; indusium concealed, cleft into narrow or slender spreading flaccid segments.
* In crevices of rocks, Michigan and western Ontario to British Columbia, south in the Rocky Mountains to Arizona and in the Sierra Nevada to California.  Also in Gaspe County, Quebec.  Summer.

### 3.5

* 5.  Woodsia oregàna  D. C. Eaton. Oregon Woodsia.   Fig. 27.
* Woodsia oregana D. C. Eaton, Can. Nat. II. 2: 90.   1865.
* Rootstock short, creeping, chaffy, the numerous leaves very densely clustered.  Stipes not jointed, brownish and chaffy below, paler or stramineous above, glabrous; blades 2′–10′ long, elliptic-lanceolate, deeply bipinnatifid or partially bipinnate, the sterile shorter than the fertile; pinnae glabrous, deltoidoblong, obtuse, deeply pinnatifid, the lower smaller and remote; segments oblong or ovate, obtuse, adnate or the largest nearly free, dentate or crenate, the teeth often revolute and covering the submarginal sori; indusia minute, concealed, consisting of a few short whitish turgid hair-like segments.
* British Columbia and Athabasca to Manitoba, Wisconsin, northern Michigan, Nebraska, Oklahoma, Colorado, Arizona and California.  Also in eastern Quebec.  July-Aug.

### 3.6

* 6.  Woodsia obtùsa  (Spreng.) Torr. Blunt-lobed Woodsia.   Fig. 28.
* Polypodium obtusum Spreng. Anleit. 3: 92.   1904.
* Woodsia obtusa Torr. Cat. Pl. in Geol. Rep. N. Y. 195.   1840.
* Rootstock short, creeping, with relatively few leaves.  Stipes not jointed, straw-colored, chaffy, 3′–6′ long; blades broadly lanceolate, 6′–15′ long, minutely glandtilar-puberulent, nearly or quite 2-pinnate; pinnae rather remote, triangular-ovate or oblong, pinnately parted into oblong obtuse crenatedentate segments, or usually pinnate, the lower pinnules free and parted nearly to the midveins; sori nearer the margin than the midveins; indusia conspicuous, at first enclosing the sporanges, at length splitting into several broad jagged spreading lobes.
* On rocks, Nova Scotia and Maine to Wisconsin and south to Georgia, Alabama, and Texas  Also in Alaska and British Columbia.  Variable.  Ascends to 2200 ft. in Virginia.

### 4.0

4.  Dennstaèdtia   Bernh.   Schrad. Journ. Bot. 1800$^2$: 124.   1801.
Mostly medium-sized ferns, with slender wide-creeping hairy rootstocks and scattered 2–3-pinnate erect leaves, 2°–6° high. Sori marginal, terminal upon the free veinlets, the sporanges clustered upon a very small receptacle within a special cup-shaped indusium formed in part of the more or less modified reflexed segment of the leaf-margin.  [Name in honor of August Wilhelm Dennstaedt.]
About 50 species mainly of tropical and subtropical regions. Type species: D. flaccida (Forst.) Bernh.
* 1.  Dennstaedtia punctilóbula  (Michx.) Moore. Hay-scented Fern.   Fig. 29.
* Nephrodium punctilobulum Michx. Fl. Bor. Am. 2: 268.  1803.
* Dicksonia pilosiuscula Willd. Enum. 1076.  1809.
* Dicksonia punctilobula A. Gray, Man. 628.  1848.
* Dennstaedtia punctilobula Moore, Ind. Fil. xcvii.  1857.
* Rootstock slender, extensively creeping, not chaffy.  Stipes stout, chaffless, usually castaneotis at the base; blades 1°–3° long, 5′–9′ wide, ovate-lanceolate to deltoid-lanceolate, acute or acuminate, frequently long-attenuate, usually 3-pinnatifid; thin and delicate, the rachis and under surface minutely glandular and pubescent; pinnae numerous, lanceolate, the segments ovate to oblong, close and deeply lobed, the margins with oblique rounded teeth; sori minute, each on a recurved tooth, usually one at the upper margin of each lobe; sporanges few, borne within the delicate cup-shaped indusium.
* In various situations, most abundant on open hillsides, Nova Scotia and New Brunswick to Ontario and Minnesota, south to Georgia. Alabama and Missouri.
* Ascends to 5600 ft. in Virginia.  Aug.  Called also Fine-haired-fern, Hairy dicksonia, Boulder-fern.

### 5.0

5.  Fìlix   Adans.   Fam. Pl. 2: 20, 558.   1763. [Cystópteris Bernh. Schrad. Neues Journ. Bot. 1$^2$: 26.  1806].
Delicate rock ferns with slender stipes, 2-4-pinnate blades, and roundish sori borne on the backs of the veins. Indusium membranous, hood-like, attached by a broad base on its inner side and partly under the sorus, early thrust back by the expanding sporanges and at least partly concealed by them, withering, the sori thus appearing naked with age. Veins free.
About 10 species mainly natives of temperate regions; the following in North America. Type species: Polypodium bulbiferum L.
Blades lanceolate, broadly lanceolate, or narrowly deltoid-lanceolate, 2-3-pinnate. :
| | • | Blades broadest at base, long-tapering, bearing bulblets beneath. | Blades broadest at base, long-tapering, bearing bulblets beneath. | Blades broadest at base, long-tapering, bearing bulblets beneath. | Blades broadest at base, long-tapering, bearing bulblets beneath. | Blades broadest at base, long-tapering, bearing bulblets beneath. | Blades broadest at base, long-tapering, bearing bulblets beneath. | Blades broadest at base, long-tapering, bearing bulblets beneath. | Blades broadest at base, long-tapering, bearing bulblets beneath. | Blades broadest at base, long-tapering, bearing bulblets beneath. | 1. | F. bulbifera. |
| | • | Blades scarcely broader at base, short-pointed; no bulblets. | Blades scarcely broader at base, short-pointed; no bulblets. | Blades scarcely broader at base, short-pointed; no bulblets. | Blades scarcely broader at base, short-pointed; no bulblets. | Blades scarcely broader at base, short-pointed; no bulblets. | Blades scarcely broader at base, short-pointed; no bulblets. | Blades scarcely broader at base, short-pointed; no bulblets. | Blades scarcely broader at base, short-pointed; no bulblets. | Blades scarcely broader at base, short-pointed; no bulblets. | 2. | F. fragilis. |
| • | Blades deltoid-ovate, 3-4-pinnate. | Blades deltoid-ovate, 3-4-pinnate. | Blades deltoid-ovate, 3-4-pinnate. | Blades deltoid-ovate, 3-4-pinnate. | Blades deltoid-ovate, 3-4-pinnate. | Blades deltoid-ovate, 3-4-pinnate. | Blades deltoid-ovate, 3-4-pinnate. | Blades deltoid-ovate, 3-4-pinnate. | Blades deltoid-ovate, 3-4-pinnate. | Blades deltoid-ovate, 3-4-pinnate. | 3. | F. montana. |

### 5.1

* 1.  Filix bulbífera  (L.) Underw. Bulblet Cystopteris. Fig. 30.   Fig. 30.
* Polypodium bulbiferum L. Sp. Pl. 1091.   1753.
* Cystopteris bulbifera Bernh. Schrad. Neues Journ. Bot. 1²: 26.   1806.
* Filix bulbifera Underw. Nat. Ferns, ed. 6, 119.   1900.
* Rootstock short, somewhat chaffy at the apex.  Stipes clustered, 4′–6′ long, light-colored; blades 1°–2½° long, usually 3-pinnatifid, deltoid-lanceolate, the gradually tapering narrow apex sometimes greatly elongate; pinnae numerous, oblong-ovate to lanceolate-oblong, horizontal, pinnate; pinnules close or somewhat apart, unequally oblong-ovate, obtuse, at least the largest deeply pinnatifid and free, the others more or less adnate and variously incised; rachis and pinnae underneath bearing large fleshy bulblets, these falling and giving rise to new plants; indusia short, convex, truncate.
* On wet rocks and in ravines, especially on limestone, Newfoundland to Manitoba, Wisconsin and Iowa, south to northern Georgia, Alabama and Arkansas. Ascends to 3500 ft. in Virginia.  July-Aug.

### 5.2

* 2.  Filix frágilis  Underw. Brittle Fern.   Fig. 31.
* Polypodium fragile L. Sp. Pl. 1091.  1753.
* Cystopteris fragilis Bernh. Schrad. Neues Journ. Bot. 1²: 27.  1806.
* Filix fragilis Underw. Nat. Ferns, ed. 6, 1 19.  1900.
* Rootstock extensively creeping, chaffy, especially at the apex.  Stipes 4′–10′ long, slender, brittle; blades thin, broadly lanceolate, slightly tapering below, 4′–10′ long, 2-3-pinnatifid or pinnate; pinnae deltoid-lanceolate to deltoidovate, acute, deeply pinnatifid or pinnate, the segments ovate or oblong-ovate, pinnatifid or incised, acutish, mostly decurrent upon the usually winged rachis; indusia roundish or nearly ovate, deeply convex, delicate.
* On rocks and in moist grassy woods, Newfoundland and Labrador to Alaska, south to Georgia, Alabama, Kansas, Arizona, and southern California.  Also in Greenland.  Almost cosmopolitan in distribution and very variable.  Ascends to 5000 ft. in New Hampshire.  May-July.  Called also Bottle-, Brittle-, or Bladder-fern.

### 5.3

* 3.  Filix montàna  (Lam.) Underw. Mountain Cystopteris.   Fig. 32.
* Polypodium montanum Lam. Fl. Franc, 1: 23.  1778.
* Cystopteris montana Bernh.; Desv. Mem. Soc. Linn. Paris 6: 264.  1827.
* Filix montana Underw. Nat. Ferns, ed. 6, 119.  1900.
* Rootstock slender, widely creeping, the leaves few and distant. Stipes 6′–9′ long, slender; blades broadly deltoid-ovate, 3-4-pinnate, about 4′–6′ long and broad, the basal pinnae much the largest, unequally deltoidovate, their inferior pinnules 1′–2′ long; pinnules deeply divided into oblong or ovateoblong lobes, these deeply toothed or again pinnate; sori numerous; indusia ovate, deeply convex, delicate, very early thrust back and concealed or evanescent.
* On rocks, Labrador and Quebec to British Columbia and Alaska, south to the northern shore of Lake Superior. Also in Colorado, and in northern Europe and Asia.  Aug.  Called also Wilson's-, Mountain-, or Bladder-fern.

### 6.0

6.  Polýstichum   Roth   Romer's Arch. Bot. 2$^1$: 106.   1799.
Coarse and usually rigid erect ferns of harsh texture, with pinnatifid to quadripinnatifid leaves borne typically in a crown upon a suberect or decumbent rootstock, the stipe not jointed to it. Sterile and fertile leaves similar, the vascular parts usually chaffy; divisions of the blade mainly auriculate and spinulose or mucronate, with free veins. Sori round; indusium superior, orbicular, attached at its middle.  [Greek, signifying many rows, in allusion to the numerous regular rows of sori in P. Lonchitis (L.) Roth, the typical species.]
About 100 species, of wide distribution, mainly in temperate regions.
Leaves simply pinnate. :
| | • | Lower pinnae gradually much reduced; upper (soriferous) pinnae conform. | Lower pinnae gradually much reduced; upper (soriferous) pinnae conform. | Lower pinnae gradually much reduced; upper (soriferous) pinnae conform. | Lower pinnae gradually much reduced; upper (soriferous) pinnae conform. | Lower pinnae gradually much reduced; upper (soriferous) pinnae conform. | Lower pinnae gradually much reduced; upper (soriferous) pinnae conform. | Lower pinnae gradually much reduced; upper (soriferous) pinnae conform. | Lower pinnae gradually much reduced; upper (soriferous) pinnae conform. | Lower pinnae gradually much reduced; upper (soriferous) pinnae conform. | 1. | P. Lonchitis. |
| | • | Lower pinnae scarcely reduced; upper (soriferous) pinnae of fertile fronds contracted. | Lower pinnae scarcely reduced; upper (soriferous) pinnae of fertile fronds contracted. | Lower pinnae scarcely reduced; upper (soriferous) pinnae of fertile fronds contracted. | Lower pinnae scarcely reduced; upper (soriferous) pinnae of fertile fronds contracted. | Lower pinnae scarcely reduced; upper (soriferous) pinnae of fertile fronds contracted. | Lower pinnae scarcely reduced; upper (soriferous) pinnae of fertile fronds contracted. | Lower pinnae scarcely reduced; upper (soriferous) pinnae of fertile fronds contracted. | Lower pinnae scarcely reduced; upper (soriferous) pinnae of fertile fronds contracted. | Lower pinnae scarcely reduced; upper (soriferous) pinnae of fertile fronds contracted. | 2. | P. acrostichoides. |
| • | Leaves bipinnatifid or bipinnate. | Leaves bipinnatifid or bipinnate. | Leaves bipinnatifid or bipinnate. | Leaves bipinnatifid or bipinnate. | Leaves bipinnatifid or bipinnate. | Leaves bipinnatifid or bipinnate. | Leaves bipinnatifid or bipinnate. | Leaves bipinnatifid or bipinnate. | Leaves bipinnatifid or bipinnate. | Leaves bipinnatifid or bipinnate. |
| | • | Leaves coriaceous, the pinnae deeply lobed at their base. | Leaves coriaceous, the pinnae deeply lobed at their base. | Leaves coriaceous, the pinnae deeply lobed at their base. | Leaves coriaceous, the pinnae deeply lobed at their base. | Leaves coriaceous, the pinnae deeply lobed at their base. | Leaves coriaceous, the pinnae deeply lobed at their base. | Leaves coriaceous, the pinnae deeply lobed at their base. | Leaves coriaceous, the pinnae deeply lobed at their base. | Leaves coriaceous, the pinnae deeply lobed at their base. | 3. | P. scopnlinum. |
| | • | Leaves herbaceous, fully bipinnate. | Leaves herbaceous, fully bipinnate. | Leaves herbaceous, fully bipinnate. | Leaves herbaceous, fully bipinnate. | Leaves herbaceous, fully bipinnate. | Leaves herbaceous, fully bipinnate. | Leaves herbaceous, fully bipinnate. | Leaves herbaceous, fully bipinnate. | Leaves herbaceous, fully bipinnate. | 4. | P. Braunii. |

### 6.1

* 1.  Polystichum Lonchìtis  (L.) Roth. Holly-fern.   Fig. 33.
* Polypodium Lonchitis L. Sp. Pl. 1088.  1753.
* Aspidium Lonchitis Sw. Schrad. Journ. Bot. 1800²: 30.  1801.
* Polystichum Lonchitis Roth, Röm. Arch. Bot. 2$^1$: 106.  1799.
* Dryopteris Lonchitis Kuntze, Rev. Gen. Pl. 813.  1891.
* Rootstock short, stout, densely chaffy. Stipes 1′–5′ long, bearing large ferruginous scales with smaller ones intermixed; blades rigid, coriaceous, evergreen, 6′-2° long, linear-lanceolate, once pinnate; pinnae numerous, close, broadly lanceolate-falcate, 1′–1½′ long, acute, strongly auricled on the upper side at the base, obliquely truncate below, notably spinulose-dentate, the lowest commonly triangular and shorter; sori large, borne usually in two rows, nearly equidistant between the margin and midrib, subconfluent with age; indusium entire.
* On rocks, Labrador to Alaska, south to Nova Scotia, Ontario, Wisconsin, Montana and Washington, and in the mountains to Utah, Colorado and California. Also in. Greenland, Europe and Asia.  Aug.  Called also Rough alpine fern.

### 6.2

* 2.  Polystichum acrostichoìdes  (Michx.) Schott. Christmas-fern.   Fig. 34.
* Nephrodium acrostichoides Michx. Fl. Bor. Am. 2: 267.  1803.
* Aspidium acrostichoides Sw. Syn. Fil. 44.  1806.
* Polystichum acrostichoides Schott, Gen. Fil.  1834.
* Dryopteris acrostichoides Kuntze, Rev. Gen. Pl. 812.  1891.
* Rootstock stout, creeping. Stipes 5′–7′ long, densely chaffy; blades lanceolate, 1°–2° long, 3′–5′ wide, rigid, evergreen, subcoriaceous, once pinnate; pinnae 1′–3′ long, narrowly oblong-lanceolate, somewhat falcate, acutish at the apex, half halberd-shaped at the base, with appressed, bristly teeth, the lower pinnae scarcely smaller, sometimes deflexed; fertile fronds contracted at the apex, the reduced pinnae soriferous, their under surface nearly covered with large contiguous sori in 2-4 rows, confluent with age; indusium entire, persistent.
* In woods and on hillsides, most abundant in rocky places, Nova Scotia to Ontario and Wisconsin, south to Texas and the Gulf states. Ascends to 2700 ft. in Maryland.  July-Aug.  Called also Christmas shield-fern.   Forms with cut-lobed or incised pinnae are known as var. Schweinitsii; occasional forms are 2-pinnatifid.

### 6.3

* 3.  Polystichum scopulìnum  (D. C. Eaton) Maxon. Eaton's Shield-fern.   Fig. 35.
* Aspidium aculeatum var. scopulinum D. C. Eaton, Ferns N. Am. 2: 125. pl. 62, f. 8.   1880.
* P. scopulinum Maxon, Fern Bull. 8: 29.   1900.
* Rootstock stout, ascending, with numerous cord-like roots.  Leaves 9′–17′ long, the stipe 2′–5′ long, densely chaffy at the base with both broad and narrow bright brown scales; blades 6′–12′ long, linear to narrowly oblong-lanceolate, 1½′–2½′ broad, coriaceous, the chaff largely deciduous from the rachis; pinnae numerous, 7″–15″ long, 4″–8″ broad at the base, ovate, obtuse, the basal portion pinnately lobed, the apical half serrate with pointed or aculeate teeth, the lower pinnae usually much reduced; sori near the midvein; indusium large, somewhat lobed, glabrous.
* On rocky slopes, Washington to Idaho, Utah and Southern California.  Gaspé county, Quebec.

### 6.4

* 4.  Polystichum Braùnii  (Spenner) Fée. Braun's Holly-fern.   Prickly Shield-fern.   Fig. 36.
* Aspidium Braunii Spenner, Fl. Frib. 1: 9. 1825.
* A. aculeatum var. Braunii Doell, Rhein. Fl. 21. 1843.
* Polystichum Braunii Fée, Gen. Fil. 278. 1850-52.
* Dryopteris aculeata var. Braunii Underw. Native Ferns, ed. 4, 112. 1893.
* Dryopteris Braunii (Spenner) Underw. in Br. & Brown, Ill. Fl. ed. 1, 1: 15. 1896.
* Rootstock stout, suberect.  Stipes 4′–5′ long, chaffy with both broad and narrow brown scales; blades lanceolate, 1°–2° long, herbaceous, 2-pinnate, the rachis chaffy; pinnae numerous, close, oblong-lanceolate, slightly broadest at the base, the middle ones 2½′–4′ long, the lower gradually shorter; pinnules ovate to oblong, truncate and nearly rectangular at the base, mostly acute, sharply toothed, beset with long soft hair-like scales; sori small, mostly nearer the midvein than the margin; indusium small, entire.
* In rocky woods, Nova Scotia to Alaska, to northern New England, the mountains of Pennsylvania, to Michigan and British Columbia. Ascends to 5000 ft. in Vermont.  Aug.

### 7.0

7.  Dryópteris   Adans.   Fam. Pl. 2: 20, 550.   1763. [Aspidium Sw. Schrad. Journ. Bot. 1800$^2$: 29, in part. 1801.].
Mainly woodland ferns, commonly of upright habit, the fertile and sterile leaves usually similar, not jointed to the rootstock. Blades 1-3-pinnate or dissected, with veins free in northern species, uniting occasionally or even freely in some of the southern. Sori round or rarely elliptical in outline, borne upon the veins, indusiate or non-indusiate, the indusium (if present) in northern species orbicular-reniform, fixed at its sinus; sporanges numerous.
A genus of several hundred species, widely distributed in the tropics, its limits variously understood. Besides the following, some 13 species occur in the southern and western United States. Type species: Polypodium Filix-mas L.
Indusia present (§ Eudryópteris). :
| | • | Texture membranous; veins simple or once forked. | Texture membranous; veins simple or once forked. | Texture membranous; veins simple or once forked. | Texture membranous; veins simple or once forked. | Texture membranous; veins simple or once forked. | Texture membranous; veins simple or once forked. | Texture membranous; veins simple or once forked. | Texture membranous; veins simple or once forked. | Texture membranous; veins simple or once forked. |
| | | • | Lower pinnae gradually and conspicuously reduced. | Lower pinnae gradually and conspicuously reduced. | Lower pinnae gradually and conspicuously reduced. | Lower pinnae gradually and conspicuously reduced. | Lower pinnae gradually and conspicuously reduced. | Lower pinnae gradually and conspicuously reduced. | Lower pinnae gradually and conspicuously reduced. | Lower pinnae gradually and conspicuously reduced. | 1. | D. noveboracensis. |
| | | • | Lower pinnae scarcely reduced. | Lower pinnae scarcely reduced. | Lower pinnae scarcely reduced. | Lower pinnae scarcely reduced. | Lower pinnae scarcely reduced. | Lower pinnae scarcely reduced. | Lower pinnae scarcely reduced. | Lower pinnae scarcely reduced. |
| | | | • | Veins once or twice forked. | Veins once or twice forked. | Veins once or twice forked. | Veins once or twice forked. | Veins once or twice forked. | Veins once or twice forked. | Veins once or twice forked. | 2. | D. Thelypteris. |
| | | | • | Veins simple. | Veins simple. | Veins simple. | Veins simple. | Veins simple. | Veins simple. | Veins simple. | 3. | D. simulata. |
| | • | Texture firmer, sometimes subcoriaceous; veins freely forked. | Texture firmer, sometimes subcoriaceous; veins freely forked. | Texture firmer, sometimes subcoriaceous; veins freely forked. | Texture firmer, sometimes subcoriaceous; veins freely forked. | Texture firmer, sometimes subcoriaceous; veins freely forked. | Texture firmer, sometimes subcoriaceous; veins freely forked. | Texture firmer, sometimes subcoriaceous; veins freely forked. | Texture firmer, sometimes subcoriaceous; veins freely forked. | Texture firmer, sometimes subcoriaceous; veins freely forked. |
| | | • | Blades 2-pinnatifid or 2-pinnate; segments not spinulose. | Blades 2-pinnatifid or 2-pinnate; segments not spinulose. | Blades 2-pinnatifid or 2-pinnate; segments not spinulose. | Blades 2-pinnatifid or 2-pinnate; segments not spinulose. | Blades 2-pinnatifid or 2-pinnate; segments not spinulose. | Blades 2-pinnatifid or 2-pinnate; segments not spinulose. | Blades 2-pinnatifid or 2-pinnate; segments not spinulose. | Blades 2-pinnatifid or 2-pinnate; segments not spinulose. |
| | | | • | Leaves small; rachis commonly chaffy throughout. | Leaves small; rachis commonly chaffy throughout. | Leaves small; rachis commonly chaffy throughout. | Leaves small; rachis commonly chaffy throughout. | Leaves small; rachis commonly chaffy throughout. | Leaves small; rachis commonly chaffy throughout. | Leaves small; rachis commonly chaffy throughout. | 4. | D. fragrans. |
| | | | • | Leaves larger, 1½°-5° high; rachis naked or deciduously chaffy. | Leaves larger, 1½°-5° high; rachis naked or deciduously chaffy. | Leaves larger, 1½°-5° high; rachis naked or deciduously chaffy. | Leaves larger, 1½°-5° high; rachis naked or deciduously chaffy. | Leaves larger, 1½°-5° high; rachis naked or deciduously chaffy. | Leaves larger, 1½°-5° high; rachis naked or deciduously chaffy. | Leaves larger, 1½°-5° high; rachis naked or deciduously chaffy. |
| | | | | • | Indusia flat, thin. | Indusia flat, thin. | Indusia flat, thin. | Indusia flat, thin. | Indusia flat, thin. | Indusia flat, thin. |
| | | | | | • | Blades narrow, linear-oblong to lanceolate; sori nearly medial. | Blades narrow, linear-oblong to lanceolate; sori nearly medial. | Blades narrow, linear-oblong to lanceolate; sori nearly medial. | Blades narrow, linear-oblong to lanceolate; sori nearly medial. | Blades narrow, linear-oblong to lanceolate; sori nearly medial. | 5. | D. cristata. |
| | | | | | • | Blades broader, narrowly oblong, ovate or triangular ovate; sori near midvein. | Blades broader, narrowly oblong, ovate or triangular ovate; sori near midvein. | Blades broader, narrowly oblong, ovate or triangular ovate; sori near midvein. | Blades broader, narrowly oblong, ovate or triangular ovate; sori near midvein. | Blades broader, narrowly oblong, ovate or triangular ovate; sori near midvein. |
| | | | | | | • | Apex attenuate; pinnae broadest at base; sori 3-7 pairs. | Apex attenuate; pinnae broadest at base; sori 3-7 pairs. | Apex attenuate; pinnae broadest at base; sori 3-7 pairs. | Apex attenuate; pinnae broadest at base; sori 3-7 pairs. | 6. | D. Clintoniana. |
| | | | | | | • | Apex short-acuminate, often abruptly so; pinnae broadest above the base; sori 6-10 pairs. | Apex short-acuminate, often abruptly so; pinnae broadest above the base; sori 6-10 pairs. | Apex short-acuminate, often abruptly so; pinnae broadest above the base; sori 6-10 pairs. | Apex short-acuminate, often abruptly so; pinnae broadest above the base; sori 6-10 pairs. | 7. | D. Goldiana. |
| | | | | • | Indusia convex, firm. | Indusia convex, firm. | Indusia convex, firm. | Indusia convex, firm. | Indusia convex, firm. | Indusia convex, firm. |
| | | | | | • | Sori near the margin. | Sori near the margin. | Sori near the margin. | Sori near the margin. | Sori near the margin. | 8. | D. marginalis. |
| | | | | | • | Sori near the midvein. | Sori near the midvein. | Sori near the midvein. | Sori near the midvein. | Sori near the midvein. | 9. | D. Filix-mas. |
| | | • | Blades 2-pinnate to 3-pinnate ; segments spinulose or mucronate. | Blades 2-pinnate to 3-pinnate ; segments spinulose or mucronate. | Blades 2-pinnate to 3-pinnate ; segments spinulose or mucronate. | Blades 2-pinnate to 3-pinnate ; segments spinulose or mucronate. | Blades 2-pinnate to 3-pinnate ; segments spinulose or mucronate. | Blades 2-pinnate to 3-pinnate ; segments spinulose or mucronate. | Blades 2-pinnate to 3-pinnate ; segments spinulose or mucronate. | Blades 2-pinnate to 3-pinnate ; segments spinulose or mucronate. |
| | | | • | Blades ovate-lanceolate, triangular, or broadly oblong, usually not narrowed below. | Blades ovate-lanceolate, triangular, or broadly oblong, usually not narrowed below. | Blades ovate-lanceolate, triangular, or broadly oblong, usually not narrowed below. | Blades ovate-lanceolate, triangular, or broadly oblong, usually not narrowed below. | Blades ovate-lanceolate, triangular, or broadly oblong, usually not narrowed below. | Blades ovate-lanceolate, triangular, or broadly oblong, usually not narrowed below. | Blades ovate-lanceolate, triangular, or broadly oblong, usually not narrowed below. |
| | | | | • | Indusia glabrous or nearly so; pinnae usually somewhat oblique to the rachis, the lowest broadly and unequally ovate to triangular. | Indusia glabrous or nearly so; pinnae usually somewhat oblique to the rachis, the lowest broadly and unequally ovate to triangular. | Indusia glabrous or nearly so; pinnae usually somewhat oblique to the rachis, the lowest broadly and unequally ovate to triangular. | Indusia glabrous or nearly so; pinnae usually somewhat oblique to the rachis, the lowest broadly and unequally ovate to triangular. | Indusia glabrous or nearly so; pinnae usually somewhat oblique to the rachis, the lowest broadly and unequally ovate to triangular. | Indusia glabrous or nearly so; pinnae usually somewhat oblique to the rachis, the lowest broadly and unequally ovate to triangular. |
| | | | | | • | Pinnules flat, decurrent ; sori terminal on the veinlets ; scales pale brownish. | Pinnules flat, decurrent ; sori terminal on the veinlets ; scales pale brownish. | Pinnules flat, decurrent ; sori terminal on the veinlets ; scales pale brownish. | Pinnules flat, decurrent ; sori terminal on the veinlets ; scales pale brownish. | Pinnules flat, decurrent ; sori terminal on the veinlets ; scales pale brownish. | 10. | D. spinulosa. |
| | | | | | • | Pinnules concave, some not decurrent ; sori mostly subterminal ; scales dark brownish. | Pinnules concave, some not decurrent ; sori mostly subterminal ; scales dark brownish. | Pinnules concave, some not decurrent ; sori mostly subterminal ; scales dark brownish. | Pinnules concave, some not decurrent ; sori mostly subterminal ; scales dark brownish. | Pinnules concave, some not decurrent ; sori mostly subterminal ; scales dark brownish. | 11. | D. dilatata. |
| | | | | • | Indusia glandular ; pinnae usually at right angles, the lowest unequally lanceolate to ovate-lanceolate. | Indusia glandular ; pinnae usually at right angles, the lowest unequally lanceolate to ovate-lanceolate. | Indusia glandular ; pinnae usually at right angles, the lowest unequally lanceolate to ovate-lanceolate. | Indusia glandular ; pinnae usually at right angles, the lowest unequally lanceolate to ovate-lanceolate. | Indusia glandular ; pinnae usually at right angles, the lowest unequally lanceolate to ovate-lanceolate. | Indusia glandular ; pinnae usually at right angles, the lowest unequally lanceolate to ovate-lanceolate. | 12. | D. intermedia. |
| | | | • | Blades elongate-lanceolate, usually narrowed below. | Blades elongate-lanceolate, usually narrowed below. | Blades elongate-lanceolate, usually narrowed below. | Blades elongate-lanceolate, usually narrowed below. | Blades elongate-lanceolate, usually narrowed below. | Blades elongate-lanceolate, usually narrowed below. | Blades elongate-lanceolate, usually narrowed below. | 13. | D. Boottii. |
| • | Indusia wanting (§ Phegopteris). | Indusia wanting (§ Phegopteris). | Indusia wanting (§ Phegopteris). | Indusia wanting (§ Phegopteris). | Indusia wanting (§ Phegopteris). | Indusia wanting (§ Phegopteris). | Indusia wanting (§ Phegopteris). | Indusia wanting (§ Phegopteris). | Indusia wanting (§ Phegopteris). | Indusia wanting (§ Phegopteris). |
| | • | Basal pinnae sessile or partially adnate : rachis more or less alate. | Basal pinnae sessile or partially adnate : rachis more or less alate. | Basal pinnae sessile or partially adnate : rachis more or less alate. | Basal pinnae sessile or partially adnate : rachis more or less alate. | Basal pinnae sessile or partially adnate : rachis more or less alate. | Basal pinnae sessile or partially adnate : rachis more or less alate. | Basal pinnae sessile or partially adnate : rachis more or less alate. | Basal pinnae sessile or partially adnate : rachis more or less alate. | Basal pinnae sessile or partially adnate : rachis more or less alate. |
| | | • | Blades usually longer than broad; rachis and midveins freely chaffy; under surfaces pilose. | Blades usually longer than broad; rachis and midveins freely chaffy; under surfaces pilose. | Blades usually longer than broad; rachis and midveins freely chaffy; under surfaces pilose. | Blades usually longer than broad; rachis and midveins freely chaffy; under surfaces pilose. | Blades usually longer than broad; rachis and midveins freely chaffy; under surfaces pilose. | Blades usually longer than broad; rachis and midveins freely chaffy; under surfaces pilose. | Blades usually longer than broad; rachis and midveins freely chaffy; under surfaces pilose. | Blades usually longer than broad; rachis and midveins freely chaffy; under surfaces pilose. | 14. | D. Phegopteris. |
| | | • | Blades usually broader than long; rachis and midveins scarcely scaly; under surfaces slightly pubescent. | Blades usually broader than long; rachis and midveins scarcely scaly; under surfaces slightly pubescent. | Blades usually broader than long; rachis and midveins scarcely scaly; under surfaces slightly pubescent. | Blades usually broader than long; rachis and midveins scarcely scaly; under surfaces slightly pubescent. | Blades usually broader than long; rachis and midveins scarcely scaly; under surfaces slightly pubescent. | Blades usually broader than long; rachis and midveins scarcely scaly; under surfaces slightly pubescent. | Blades usually broader than long; rachis and midveins scarcely scaly; under surfaces slightly pubescent. | Blades usually broader than long; rachis and midveins scarcely scaly; under surfaces slightly pubescent. | 15. | D. hexagonoptera. |
| | • | Basal pinnae long-stalked; rachis not alate. | Basal pinnae long-stalked; rachis not alate. | Basal pinnae long-stalked; rachis not alate. | Basal pinnae long-stalked; rachis not alate. | Basal pinnae long-stalked; rachis not alate. | Basal pinnae long-stalked; rachis not alate. | Basal pinnae long-stalked; rachis not alate. | Basal pinnae long-stalked; rachis not alate. | Basal pinnae long-stalked; rachis not alate. |
| | | • | Blades nearly horizontal, glabrous or nearly so, subternate, the basal pinnae approaching the terminal portion in size. | Blades nearly horizontal, glabrous or nearly so, subternate, the basal pinnae approaching the terminal portion in size. | Blades nearly horizontal, glabrous or nearly so, subternate, the basal pinnae approaching the terminal portion in size. | Blades nearly horizontal, glabrous or nearly so, subternate, the basal pinnae approaching the terminal portion in size. | Blades nearly horizontal, glabrous or nearly so, subternate, the basal pinnae approaching the terminal portion in size. | Blades nearly horizontal, glabrous or nearly so, subternate, the basal pinnae approaching the terminal portion in size. | Blades nearly horizontal, glabrous or nearly so, subternate, the basal pinnae approaching the terminal portion in size. | Blades nearly horizontal, glabrous or nearly so, subternate, the basal pinnae approaching the terminal portion in size. | 16. | D. Dryopteris. |
| | | • | Blades suberect, copiously glandular, triangular-ovate, the basal pinnae considerably smaller than the terminal portion. | Blades suberect, copiously glandular, triangular-ovate, the basal pinnae considerably smaller than the terminal portion. | Blades suberect, copiously glandular, triangular-ovate, the basal pinnae considerably smaller than the terminal portion. | Blades suberect, copiously glandular, triangular-ovate, the basal pinnae considerably smaller than the terminal portion. | Blades suberect, copiously glandular, triangular-ovate, the basal pinnae considerably smaller than the terminal portion. | Blades suberect, copiously glandular, triangular-ovate, the basal pinnae considerably smaller than the terminal portion. | Blades suberect, copiously glandular, triangular-ovate, the basal pinnae considerably smaller than the terminal portion. | Blades suberect, copiously glandular, triangular-ovate, the basal pinnae considerably smaller than the terminal portion. | 17. | D. Robertiana. |

### 7.1

* 1.  Dryopteris noveboracénsis  (L.) A. Gray. New York Fern.   Fig. 37.
* Polypodium noveboracense L. Sp. Pl. 1091.  1753.
* Aspidium noveboracense Sw. Schrad. Journ. Bot. 1800²: 38.  1801.
* Dryopteris noveboracensis A. Gray, Man. 632.  1848.
* Rootstock slender, widely creeping. Stipes slender, short; blades lanceolate, tapering both ways from the middle, 1°–2° long, 4′–7′ wide, membranous, once pinnate, the apex long-acuminate; pinnae 1½′–3½′ long, lanceolate, sessile, long-acuminate, deeply pinnatifid, pilose along the midribs and veins, especially beneath, ciliate, the lower (2-7) pairs gradually shorter and deflexed, commonly distant, the lowest auriculiform; segments flat, oblong, obtuse, the basal ones often enlarged; veins simple or those of the basal lobes forked; sori near the margin; indusia small, delicate, glandular, withering.
* In moist woods and thickets, Newfoundland to Ontario and Minnesota, south to Georgia, Alabama and Arkansas. Ascends to 5000 ft. in Virginia. Sometimes sweet-scented in drying.  July-Sept.

### 7.2

* 2.  Dryopteris Thelýpteris  (L.) A. Gray. Marsh Shield-fern.   Fig. 38.
* Acrostichum Thelypteris L. Sp. Pl. 1071.   1753.
* Aspidium Thelypteris Sw. Schrad. Journ. Bot. 1800²: 40.   1801.
* Dryopteris Thelypteris A. Gray, Man. 630.   1848.
* Rootstock slender, creeping, blackish. Leaves long-stipitate, the blades lanceolate or oblong-lanceolate, scarcely narrowed at base, 1°-2½° long, 4'-6' wide, short-acuminate, membranous, once pinnate; pinnae 1½'-3' long, linear-lanceolate, short-stalked or sessile, horizontal or decurved, broadest at the base, shortacuminate, pubescent or pilose beneath, deeply pinnatifid; segments oblong, obtuse or appearing acute from the strongly revolute margins; veins regularly once or twice forked; sori nearly medial, crowded; indusia small, glabrous.
* In marshes and wet woods, rarely in dry soil, New Brunswick to Manitoba, south to Florida, Louisiana and Texas. Ascends to 2000 ft. in Vermont. Europe and Asia.  Summer.  Wood-, Swamp-, Quill- or Marsh-Fern.

### 7.3

* 3.  Dryopteris simulàta  Davenp. Dodge's Shield-fern.   Fig. 39.
* Aspidium simulatum Davenp. Bot. Gaz. 19: 495.  1894.
* Dryopteris simulata Davenp. Bot. Gaz. 19: 497.  1894.  As synonym.
* Rootstock wide-creeping, slender, brownish; stipes 6′–20′ long, straw-colored, dark brown at base, with deciduous scales; blades 8′–20′ long, 2′–7′ wide, oblong-lanceolate, membranous, once pinnate, little or not at all narrowed at the base, the apex abruptly acuminate, attenuate; pinnae 12-20 pairs, lanceolate, deeply pinnatifid, the segments oblique, oblong, obtuse, entire or lightly crenate, slightly revolute in the fertile leaf, ciliate, finely pubescent along the midribs; veins simple; sori rather large, somewhat apart, mostly nearer the margin than the midrib; indusia finely glandular, withering, persistent.
* In woodland swamps, Maine to Maryland. Reported also from Missouri.  Late summer.

### 7.4

* 4.  Dryopteris fràgrans  (L.) Schott. Fragrant Shield-fern.   Fig. 40.
* Polypodium fragrans L. Sp. Pl. 1089.  1753.
* Aspidium fragrans Sw. Schrad. Journ. Bot. 1800²: 35.  1801.
* Dryopteris fragrans Schott, Gen. Fil.  1834.
* Rootstock stout, erect, densely chaffy with brown shining scales.  Stipes 2′–4′ long, chaffy; blades lanceolate to narrowly oblanceolate, 3′–12′ long, firm, aromatic, nearly or quite 2-pinnate, the apex acute; pinnae numerous, ½′–1¼′ long, oblong-lanceolate to deltoid-lanceolate, usually subacute; segments oblong, obtuse, adnate, decurrent, deeply incised to subentire, nearly covered by the sori; indusium thin, very large, nearly orbicular, long-persistent, its margin ragged and sparingly glandular, the sinus narrow.
* On rocks, Labrador to Alaska, south to Maine, New Hampshire, Vermont, New York, Wisconsin and Minnesota. Ascends to 4000 ft. in Vermont.  Also in Greenland, Europe and Asia.  Fragrant wood-fern.

### 7.5

* 5.  Dryopteris cristàta  (L.) A. Gray. Crested Shield-fern.   Fig. 41.
* Polypodium cristatum L. Sp. Pl. 1090.  1753.
* Aspidium cristatum Sw. Schrad. Journ. Bot. 1800²: 37.  1801.
* Dryopteris cristata A. Gray, Man. 631.  1848.
* Rootstock stout, creeping, densely chaffy.  Sterile leaves low, short-stipitate, spreading, much shorter than the fertile, evergreen.  Fertile leaves rigidly erect, 1½°–3½° long, long-stipitate, withering; blades 1°–1½° long, 3′–6′ broad, linear-oblong to lanceolate, acuminate, deeply bipinnatifid, dark green; pinnae spaced, oblong-lanceolate to triangular-ovate or the lower ones subtriangular; deeply pinnatifid into 6–10 pairs of oblong to triangular-oblong, obtuse, finely serrate segments, the basal ones more deeply cut; sori nearly medial; indusia large, orbicular-reniform, glabrous.
* In wet woods and swamps, Newfoundland to Saskatchewan, south to Virginia, Kentucky, Arkansas, Nebraska and Idaho  Ascends to 2700 ft. in Maryland.  Also in Europe and Asia.  July–Aug.  Crested-fern or crested wood-fern.

### 7.6

* 6.  Dryopteris Clintoniàna  (D. C. Eaton) Dowell. Clinton's Fern.   Fig. 42.
* Aspidium cristatum var. Clintonianum D. C. Eaton in Gray, Man. ed. 5, 665.  1867.
* Dryopteris cristata var. Clintoniana Underw. Native Ferns, ed. 4, 115.  1893.
* Dryopteris Clintoniana Dowell, Proc. Staten Id. Assoc. Arts & Sc. 1: 64.  1906.
* Rootstocks stout, creeping, densely chaffy.  Leaves 2½°–4½° high; stipes 1° or more long, straw-colored or brownish, with thin concolorous or often dark-centered scales; blades 1½°–3° long, 5′–10′ broad, oblong to ovate-oblong, acute or acuminate, deeply bipinnatifid; pinnae apart, oblong-lanceolate, broadest at the base, or lower ones unequally elongatetriangular, deeply pinnatifid; segments oblong, usually obtuse, serrate, or the basal ones pinnately cut; sori 3-7 pairs.
* borne near the midvein; indusia orbicular-reniform, glabrous.
* In swampy woods, Maine and Ontario to Wisconsin, and North Carolina.  Often confused with the preceding and the following species.

### 7.7

* 7.  Dryopteris goldiàna  (Hook.) A. Gray. Goldie's Fern.   Fig. 43.
* Aspidium Goldianum Hook. Edinb. Philos. Journ. 6: 333.  1822.
* Dryopteris Goldiana A. Gray, Man. 631.  1848.
* Rootstock stout, ascending, chaffy. Leaves up to 5½° long, in a crown; stipes 10′–18′ long, densely covered below with large lanceolate usually dark lustrous scales; lamina 2°–4° long, 10′–16′ broad, ovate to oblong, short-acuminate, nearly glabrous, dark green above, nearly 2-pinnate; pinnae 6′–9′ long, 1-2′ broad, broadly lanceolate to oblong-lanceolate, broadest above the base, acuminate, pinnatifid almost to the midrib; segments about 20 pairs, narrowly oblong, acute or subacute, subfalcate, serrate, the teeth appressed; sori 6-10 pairs, near the midrib, distinct; indusia glabrous, nearly orbicular, the sinus narrow.
* In rich woods.  New Brunswick to Minnesota, south to North Carolina, Tennessee and Iowa.  Ascends to 5000 ft. in Virginia and to 2500 ft. in Vermont.  July-Aug.  Goldie's Wood-fern.

### 7.8

* 8.  Dryopteris marginàlis  (L.) A. Gray. Evergreen Wood-fern.   Fig. 44.
* Polypodium marginals L. Sp. Pl. 1091.  1753.
* Aspidium marginale Sw. Syn. Fil. 50.  1806.
* Dryopteris marginalis A. Gray, Man. 632.  1848.
* Rootstock stout, woody, ascending, densely covered with bright brown shining scales, the leaves borne in a crown.  Stipes 4′–10′ long, chaffy below; blades ovate-oblong or ovate-lanceolate, chartaceo-coriaceous, 6′–2½° long, nearly or quite 2-pinnate, acuminate, usually a little narrowed at the base; pinnae numerous, sessile or nearly so, glabrous, 2′–5′ long, the lowermost unequally deltoid-lanceolate, those above lanceolate to broadly oblong-lanceolate, acuminate; segments oblong or lanceolate, obtuse or subacute, subfalcate or falcate, subentire, crenate or pinnately lobed, partially adnate or the lowermost distinct; sori distant, close to the margin; indusia orbicular-reniform, glabrous.
* In rocky woods and on banks Nova Scotia to British Columbia, south to Georgia, Alabama, Arkansas, Kansas and Oklahoma.  Ascends to 5000 ft. in Virginia.  Leaves evergreen.  July-Aug.  Marginal Shield-fern.

### 7.9

* 9.  Dryopteris Fìlix-más  (L.) Schott. Male Fern.   Fig. 45.
* Polypodium Filix-mas L. Sp. Pl. 1090.  1753.
* Aspidium Filix-mas Sw. Schrad. Journ. Bot. 1800²: 38.  1801.
* Dryopteris Filix-mas Schott, Gen. Fil.  1834.
* Rootstock stout, woody, ascending or erect, chaffy.  Leaves up to 4° high, in an erect crown; stipes 4′–10′ long, densely chaffy below; blades nearly evergreen, 1°–3° long, 6′–11′ broad, broadly oblong-lanceolate, acuminate, narrowed at the base, nearly or quite 2-pinnate; pinnae narrowly deltoid-lanceolate to oblonglanceolate, acuminate; segments adnate, oblong, obtuse and biserrate, or partially adnate, ovate-oblong, acutish and deeply incised; sori numerous, large, nearer the midvein than the margin; indusia orbicular-reniform, glabrous.
* In rocky woods, Newfoundland and Labrador to Alaska, south to Vermont, northern Michigan, South Dakota, Arizona and California.  Aug.  Also in Greenland. Numerous related forms of wide distribution are referred to this species; the type is European.  The rootstock of this and the preceding species furnish the drug Filix-mas used as a vermifuge.  Basket-fern. Male shield-fern. Shield-roots. Bear's-paw-roots. Sweet or knotty brake.

### 7.10

* 10.  Dryopteris spinulosa  (Muell.) Kuntze. Spinulose Shield-fern.   Fig. 46.
* Polypodium spinulosum Muell. Fl. Fridr. 113. f. 2.  1767.
* Aspidium spinulosum Sw. Schrad. Journ. Bot. 1800²: 38.  1801.
* Dryopteris spinulosa Kuntze, Rev. Gen. Pl. 2: 813.  1891.
* Rootstock stout, creeping, chaffy.  Leaves in an incomplete crown, the taller erect, the others spreading, stipes 4′–14′ long, with pale brownish scales; blades ½°–1½° long, 3½′–9′ broad, ovate-lanceolate to oblong, acuminate, deeply 2-pinnatifid; pinnae usually oblique, pinnately divided, the lower ones unequally deltoid, those above lanceolate from a broad base, acuminate; pinnules flat, oblong to lanceolate, acute, dectirrent, pinnately cut, segments incised, teeth mucronate, falcate, appressed; sori submarginal, terminal on veinlets; indusia without glands.
* In rich low woods, Labrador to Selkirk and Idaho, to Virginia and Kentucky.  Also in Europe.  Called also Narrow Prickly-toothed Fern.

### 7.11

* 11.  Dryopteris dilatàta  (Hoffm.) Gray. Spreading Shield-fern.   Fig. 47.
* Polypodium dilatatum Hoffm. Deutschl. Fl. 2: 7.  1795.
* Aspidium spinulosum var. dilatatum Hook. Brit. FL 444.  1830.
* Dryopteris spinulosa var. dilatata Underw. Nat. Ferns, ed. 4, 116.  1893.
* Rootstock creeping, or ascending. Leaves equal, spreading, in a complete crown; stipes ½°–1½° long, with dark brownish often darker-centered scales; blades ¾°–2¾° long, 4′–16′ broad, triangular to ovate or broadly oblong, acuminate, 3-pinnatifid; pinnae variable, the lower ones broadly and unequally ovate or triangular, those above lanceolate to oblong, acute or acuminate, the lowermost at least pinnately divided; pinnules convex, oblong to lanceolate, acute, the largest not decurrent, pinnately divided, segments pinnately lobed, teeth mucronate, straight or falcate, usually not appressed; sori mostly subterminal; indusia glabrous, or with a few glands.
* A high mountain species of rocky woods, Newfoundland to Alaska, California, Idaho, Tennessee and North Carolina, Greenland.  Also in Eurasia, Japan and the Madeira Islands.  Broad Prickly-toothed Wood-fern.

### 7.12

* 12.  Dryopteris intermèdia  (Muhl.) Gray. American Shield-fern.   Fig. 48.
* Polypodium intermedium Muhl.; Willd. Sp. Pl. 5: 262.  1810.
* Aspidium americanum Davenp. Am. Nat. 12: 714.  1878.
* Dryopteris spinulosa var. intermedia Underw. Nat. Ferns, ed. 4, 116.  1893.
* Rootstock creeping  Leaves equal, spreading in a complete crown; stipes 4′–14′ long, with light brownish or darker-centered scales; blades similar in size and shape to those of D. spinulosa, glandular-pubescent when young; pinnae usually at right angles to the rachis, the lower ones at least pinnate, unequally lanceolate to ovate-lanceolate; the upper ones lanceolate to oblong, acuminate; pinnules convex, oblong or lanceolate, acute, the largest not decurrent, pinnately divided, nearly at right angles; segments dentate, usually straight; sori submarginal, subterminal; indusia glandular.
* In moist woods, Newfoundland to Wisconsin, south to North Carolina and Tennessee.  Known only from eastern North America.  Called also Common Wood-fern.

### 7.13

* 13.  Dryopteris Boòttii  (Tuckerm.) Underw. Boott's Shield-fern.   Fig. 49.
* Rootstock stout, ascending. Stipes 8′–12′ long, covered below with thin pale-brown scales; blade of fertile leaves elongate-oblong or lanceolate, acuminate, slightly narrowed toward the base, firm,
* bipinnate, or 3-pinnatifid, 1°–2½° long, 3′–5′ wide, the sterile ones commonly shorter and less divided; middle and upper pinnae lanceolate with a broad base, acuminate, those below unequally deltoidlanceolate, the lowest elongate-triangular; pinnules oblong-ovate, constricted at the base, the lower ones nearly sessile, often pinnatifid, those above adnate and slightly decurrent upon the narrowly winged rachis, serrate, the margins spinulose throughout; sori numerous, distinct, medial or nearer the midvein; indusia orbicular-reniform, glandular.
* In low woods and wet thickets. Nova Scotia to Minnesota, south to Virginia and West Virginia.  July-Sept.
Several American writers regard D. Boottii as a natural hybrid between D. cristata and D. intermedia.   Other supposed hybrids have recently been described, which have been confused either with D. Boottii or with species of which they were regarded as aberrant forms.  The characters of these are such as to support strongly the hybridity hypothesis.  They should be sought in localities exceptionally favorable to a mingling of the supposed parent forms.  A list of these, including D. Boottii, follows:
* Dryopteris Clintoniana × Goldiana Dowell, Bull. Torrey Club 35: 137.   1908.
* Dryopteris Goldiana celsa Palmer, Proc. Biol. Soc. Wash. 13: 65.   1899.
* Dryopteris Clintoniana × intermedia Dowell, Bull. Torrey Club 35: 136.   1908.
* Dryopteris Clintoniana × marginalis Slosson, Bull. Torrey Club 37: 202.   1910.
* Dryopteris Clintoniana × spinulosa Benedict, Bull. Torrey Club 36: 45.   1909.
* Dryopteris cristata × Goldiana Benedict, Bull. Torrey Club 36: 47.   1909.
* Dryopteris cristata × intermedia Dowell. Bull. Torrey Club 35: 136.   1908.
* Aspidium Boottii Tuckerm. Hovey's Mag. 9: 145.   1843.
* Aspidium spinulosum var. Boottii D. C. Eaton in A. Gray, Man., ed. 5, 665.   1867.
* Dryopteris Boottii Underw. Nat. Ferns, ed. 4, 117.   1893.
* Dryopteris cristata × spinulosa intermedia Slosson, Fern Bull. 16 : 97.   1908.
* Dryopteris cristata × marginalis Davenp. Bot. Gaz. 19: 497.   1894, as syn.
* Aspidium cristatum × marginale Davenp. Bot. Gaz. 19: 494.   1894.
* Dryopteris cristata × spinulosa (Milde) C. Chr. Ind. Fil. 259.   1905
* Aspidium cristatum × spinulosum Milde, Nov. Act. Acad. Leop.-Carol. 26: 533.   1856.
* Dryopteris Goldiana × intermedia Dowell, Bull. Torrey Club 35: 138.   1908.
* Dryopteris Goldiana × marginalis Dowell, Bull. Torrey Club 35: 139.   1908.
* Dryopteris Goldiana × spinulosa Benedict, Bull. Torrey Club 36: 47.   1909.
* Dryopteris intermedia × marginalis Benedict, Bull. Torrey Club 36: 48.   1909.
* Dryopteris marginalis × spinulosa Slosson, Fern Bull. 16: 99.   1908.
* Dryopteris pittsfordensis Slosson, Rhodora 6: 75.   1904.
* Nephrodium pittsfordense Davenp. Rhodora 6: 76.   1904, as syn.
* Aspidium spinulosum × marginale Eggleston, Rhodora 6: 138.   1904.

### 7.14

* 14.  Dryopteris Phegópteris  (L.) C. Chr. Long Beech-fern.   Fig. 50.
* Polypodhtm Phegopteris L. Sp. Pl. 1089.  1753.
* Phegopteris polypodioides Fee, Gen. Fil. 243.  1850-52.
* Phegopteris Phegopteris Underw.; Small, Bull. Torr. Club, 20: 462.  1893.
* Dryopteris Phegopteris C. Chr. Ind. Fil. 284.  1905.
* Rootstock slender, creeping, somewhat chaffy.  Stipes stramineous, 6′–14′ long, blades triangular, thin, mostly longer than wide, 4′–9′ long, 3′–8′ wide, long-acuminate, pilose, especially on the veins beneath, the rachis and midribs with narrow rusty or brownish scales; pinnae close, lanceolate or linear-lanceolate, broadest above the base, acuminate, pinnately parted nearly to the rachis into oblong obtuse
* entire or crenate close segments, the lowest pair deflexed; basal segments, at least those of the upper pinnae, adnate to the rachis and decurrent; sori small, near the margin, non-indusiate.
* Moist woods and hillsides, Newfoundland to Alaska, the mountains of Virginia, Michigan to Washington.  Ascends to 4000 ft. in Vermont, Greenland, Europe and Asia.  Aug.  Sun-fern.  Common beech-fern.

### 7.15

* 15.  Dryopteris hexagonóptera  (Michx.) C. Chr. Broad Beech-fern.   Fig. 51.
* Polypodium hcxagonopterum Michx. Fl. Bor. Am. 2: 271.  1803.
* Phegopteris hexagonoptera Fee, Gen. Fil. 243.  1850-52.
* D. hexagonoptera C. Chr. Ind. Fil. 270.  1905.
* Rootstock slender, creeping, chaffy, somewhat fleshy.  Stipes 8′–18′ long, greenish or brownish straw-colored; blades triangular, 7′–15′ broad, usually broader than long, acuminate, slightly pubescent, often glandular beneath; pinnae adnate to the irregularly winged rachis, acuminate, the upper and middle ones lanceolate, pinnatifid into numerous obtuse oblong subentire or crenate segments, the lowermost pinnae broader, unequally ovate to lanceolate-ovate with the middle pinnules elongate, spaced, often deeply pinnatifid; sori mostly near the margin, non-indusiate.
* In dry woods and on hillsides, Quebec to Minnesota, Florida, Louisiana, Kansas and Oklahoma.  Aug.  Called also Hexagon Beech-fern.

### 7.16

* 16.  Dryopteris Dryópteris  (L.) Britton. Oak-fern.   Fig. 52.
* Polypodium Dryopteris L. Sp. Pl. 1093.  1753.
* Phegopteris Dryopteris Fée, Gen. Fil. 243.  1850-52.
* Dryopteris Linneana C. Chr. Ind. Fil. 275.  1905.
* Rootstock blackish, very slender, wide-creeping.  Stipes slender, straw-colored, 4′–12′ long, chaffy at least below; blades thin, at right angles to the stipe, nearly or quite glabrous, 4′–11′ broad, broadly triangular, subternate by the enlargement of the basal pinnae, these triangular, very deeply 2-pinnatifid, long-stalked; second pair of pinnae oblong or deltoidoblong, sessile and nearly pinnate, or (rarely) stalked and 2-pinnatifid; upper pinnae gradually adnate, pinnatifid; segments oblong, blunt, entire to serratecrenate; sori near the margin, non-indusiate.
* In moist woods, thickets and swamps, Newfoundland and Labrador to Alaska, south to Virginia, Kansas, Colorado and Oregon.  Ascends to 2400 ft. in the Catskills.  Also in Greenland, Europe and Asia.  Aug.  Pale-mountain, or tender three-branched-polypody.

### 7.17

* 17.  Dryopteris robertiana    Fig. 53.

### 8.0

8.  Anchístea   Presl,   Epim. Bot. 7•1.   1851.

### 8.1

* 1.  Anchistea virginica    Fig. 54.

## 9.0

9.  Lorinseria       .

### 9.1

* 1.  Lorinseria areolata    Fig. 55.

## 10.0

10.  Phyllitis       .

### 10.1

* 1.  Phyllitis scolopendrium    Fig. 56.

## 11.0

11.  Camptosorus       .

### 7.1

* 1.  Camptosorus rhizophyllus    Fig. 57.

## 12.0

12.  Asplenium       .

### 7.1

* 1.  Asplenium ebenoides    Fig. 58.

### 7.2

* 2.  Asplenium pinnatifidum    Fig. 59.

### 7.3

* 3.  Asplenium resiliens    Fig. 60.

### 7.4

* 4.  Asplenium platyneuron    Fig. 61.

### 7.5

* 5.  Asplenium trichomanes    Fig. 62.

### 7.6

* 6.  Asplenium viride    Fig. 63.

### 7.7

* 7.  Asplenium pycnocàrpon  Spreng. Narrow-leaved Spleenwort.   Fig. 64.
* Asplenium angustifolium Michx. Fl. Bor. Am. 2: 265. 1803. Not Jacq. 1786.
* Asplenium pycnocarpon Spreng. Anleit. 3: 112. 1804.
* Athyrium pycnocarpon Tidestrom, Elys. Marianum 36. 1906.

### 7.8

* 8.  Asplenium ruta-muraria    Fig. 65.

### 7.9

* 9.  Asplenium montanum    Fig. 66.

### 7.10

* 10.  Asplenium fontanum    Fig. 67.

### 7.11

* 11.  Asplenium bradleyi    Fig. 68.

## 13.0

13.  Athyrium       .

### 13.1

* 1.  Athyrium thelypteroides    Fig. 69.

### 13.2

* 2.  Athyrium filix-foemina    Fig. 70.

## 14.0

14.  Adiantum       .

### 14.1

* 1.  Adiantum capillus-veneris    Fig. 71.

### 14.2

* 2.  Adiantum pedatum    Fig. 72.

## 15.0

15.  Pteridium       .
* 1.  Pteridium aquilinum    Fig. 73.

## 16.0

16.  Cryptográmma   R. Br.   App. Franklin's Journ. 767.   1823.
Small mainly alpine or boreal ferns with dimorphous leaves, the stipes greenish or strawcolored, the blades 2-3-pinnate, the fertile exceeding the sterile. Sori borne at or near the ends of the free forking veins, at length confluent. Indusia formed of the altered reflexed margin of the segment.  [Greek, alluding to the sori hidden before maturity.]
Four species, the following and 2 of Europe and Asia. Type species: C. acrostichoides R. Br.
C. acrostichoides. :
| • | Rootstocks slender, creeping; fertile segments much broader. | Rootstocks slender, creeping; fertile segments much broader. | Rootstocks slender, creeping; fertile segments much broader. | Rootstocks slender, creeping; fertile segments much broader. | Rootstocks slender, creeping; fertile segments much broader. | Rootstocks slender, creeping; fertile segments much broader. | Rootstocks slender, creeping; fertile segments much broader. | Rootstocks slender, creeping; fertile segments much broader. | Rootstocks slender, creeping; fertile segments much broader. | Rootstocks slender, creeping; fertile segments much broader. | 2. | C. Stelleri. |

### 1.1

* 1.  Cryptogramma acrostichoìdes  R. Br. American Rock-brake.   Fig. 74.
* Cryptogramma acrostichoides R. Br. App. Franklin's Journ. 767. 1823.
* Rootstock stout, short, chaffy ; leaves clustered, the fertile ones surpassing the sterile. Stipes 2'-6' long, chaffy below, those of the sterile leaves slender, greenish and of the fertile stouter and stramineous; blades ovate or ovate-lanceolate, thin, glabrous, 2-3-pinnate, the
* sterile ones with the ultimate segments and pinnules crowded, ovate, oblong or obovate, obtuse, crenate or incised ; fertile blades with segments 3"-6" long, 1" or less wide, the thin margins involute to the midrib at first, at maturity expanded, exposing the sporanges.
* Among rocks, Labrador to Alaska, south to Lakes Huron and Superior, in the mountains to
* Colorado and California.  Summer.

### 1.2

* 2.  Cryptogramma stélleri.png  (S. G. Gmel.) Prantl.   Fig. 75.

## 17.0

17.  Pellaèa   Link,   Fil. Hort. Berol. 59.   1841.
Rock-loving small or medium-sized ferns, with nearly uniform leaves, the blades 1-3-pinnate, smooth, the fertile divisions commonly narrower than the sterile. Sori roundish or elongate, on the free veins, usually confluent in a submarginal line. Indusium formed by the reflexed margins of the segments.  [Greek, alluding to the dark-colored stipes.]
About 50 to 60 species of wide geographic distribution. Besides the following several occur in the western and southwestern United States. Type species: Pellaea atropurpurea (L.) Link.
P. atropurpurea. :
| • | Blades small, 3-pinnate, the pinnules narrow. | Blades small, 3-pinnate, the pinnules narrow. | Blades small, 3-pinnate, the pinnules narrow. | Blades small, 3-pinnate, the pinnules narrow. | Blades small, 3-pinnate, the pinnules narrow. | Blades small, 3-pinnate, the pinnules narrow. | Blades small, 3-pinnate, the pinnules narrow. | Blades small, 3-pinnate, the pinnules narrow. | Blades small, 3-pinnate, the pinnules narrow. | Blades small, 3-pinnate, the pinnules narrow. | 2. | P. densa. |

### 1.1

* 1.  Pellaea atropurpure    Fig. 76.

### 1.2

* 2.  Pellaea densa    Fig. 77.

## 18.0

18.  Cheilánthes   Sw.   Syn. Fil. 126.   1806.
Small rock-loving ferns, mostly with pubescent, tomentose or scaly leaves, the blades uniform, 1-3-pinnate, the divisions often minute and bead-like. Sori terminal upon the veins, marginal, roundish and distinct, or somewhat confluent, often obscured by the hairy or scaly covering. Indusia formed of the revolute or reflexed usually modified margins of the segments.  [Greek, in allusion to the marginal sori.]
About 100 or more species, of temperate and tropical regions. Besides the following numerous other species occur in the southwestern and western United States and in Mexico. Type species : Cheilanthes micropteris Sw.
C. alabamensis. :
| Blades hirsute or tomentose. | Blades hirsute or tomentose. | Blades hirsute or tomentose. | Blades hirsute or tomentose. | Blades hirsute or tomentose. | Blades hirsute or tomentose. | Blades hirsute or tomentose. | Blades hirsute or tomentose. | Blades hirsute or tomentose. | Blades hirsute or tomentose. |
| • | Blades hirsute and glandular; indusia discontinuous. | Blades hirsute and glandular; indusia discontinuous. | Blades hirsute and glandular; indusia discontinuous. | Blades hirsute and glandular; indusia discontinuous. | Blades hirsute and glandular; indusia discontinuous. | Blades hirsute and glandular; indusia discontinuous. | Blades hirsute and glandular; indusia discontinuous. | Blades hirsute and glandular; indusia discontinuous. | Blades hirsute and glandular; indusia discontinuous. | 2. | C. lanosa. |
| • | Blades tomentose; indusia mostly continuous. | Blades tomentose; indusia mostly continuous. | Blades tomentose; indusia mostly continuous. | Blades tomentose; indusia mostly continuous. | Blades tomentose; indusia mostly continuous. | Blades tomentose; indusia mostly continuous. | Blades tomentose; indusia mostly continuous. | Blades tomentose; indusia mostly continuous. | Blades tomentose; indusia mostly continuous. |
| | • | Blades 2'-5' long; stipes slender; indusia herbaceous. | Blades 2'-5' long; stipes slender; indusia herbaceous. | Blades 2'-5' long; stipes slender; indusia herbaceous. | Blades 2'-5' long; stipes slender; indusia herbaceous. | Blades 2'-5' long; stipes slender; indusia herbaceous. | Blades 2'-5' long; stipes slender; indusia herbaceous. | Blades 2'-5' long; stipes slender; indusia herbaceous. | Blades 2'-5' long; stipes slender; indusia herbaceous. | 3. | C. Feei. |
| | • | Blades 6'-15' long; stipes stout, tomentose; indusia membranous. | Blades 6'-15' long; stipes stout, tomentose; indusia membranous. | Blades 6'-15' long; stipes stout, tomentose; indusia membranous. | Blades 6'-15' long; stipes stout, tomentose; indusia membranous. | Blades 6'-15' long; stipes stout, tomentose; indusia membranous. | Blades 6'-15' long; stipes stout, tomentose; indusia membranous. | Blades 6'-15' long; stipes stout, tomentose; indusia membranous. | Blades 6'-15' long; stipes stout, tomentose; indusia membranous. | 4. | C. tomentosa. |

### 18.1

* 1.  Cheilanthes alabamensis    Fig. 78.

### 18.2

* 2.  Cheilanthes lanosa    Fig. 79.

### 18.3

* 3.  Cheilanthes feei    Fig. 80.

### 18.4

* 4.  Cheilanthes tomentosa    Fig. 81.

## 19.0

19.  Notholaena       .
* 1.  Notholaena dealbata    Fig. 82.

## 20.0

20.  Polypodium       .

### 1.1

* 1.  Polypodium vulgare    Fig. 83.

### 1.2

* 2.  Polypodium polypodioides    Fig. 84.