688 FiLiCES. (ferns.) 



^ ^_ H_ Large (2-4° high); fronds once pinnate and the pinnce deeply pinnaH- 

 Jid, or nearly twice pinnate; fruit-dots not very near the margin ; the indu- 

 sium large, thinnish and fat, persistent. 



6. A. cristatum, Swartz. Frond linear-oblong or lanceolate in outline 

 (1 - 2° long) ; pinme short (2 - 3' long), triangular-oUong, or the lowest nearly 

 triangular-ovate, from a somewhat heart-shaped base, acute, deeply pinnatifid ; 

 the divisions (6-10 pairs) oblong, very obtuse, finely serrate or cut-toothed, the 

 lowest pinnatifid-lobed ; fruit-dots as near the midvein as the margin; indusium 

 round-reniform, the sinus mostly shallow, smooth and naked. — Swamps, etc. ; 

 common. July. — Stipes and the stout creeping rootstock bearing broad and 

 deciduous chaffy scales. (Eu.) 



Var. Clintonianum. Frond in every way much larger (2^-4° long), 

 pinnm oblong-lanceolate, broadest at base (4-6' long, 1-2' broad), deeply pin- 

 natifid ; the divisions (8-16 pairs) crowded or distant, Z/near-oi/on^r, obtuse, 

 obscurely serrate or cut-toothed, the basal sometimes pinnately lobed ; veins 

 pinnately forking, the lowest anterior veinlets bearing the fruit-dots near the 

 midvein ; indusium orbicular with a shallow sinus, smooth and naked. — 

 Swampy woods. New Eng. to N. J., N. Y. {G. W. Clinton, etc.), and west- 

 ward. July. — Rootstock stout, creeping, chaffy (like the stipes) with large 

 bright-brown scales. A showy fern, unlike any European form of A. crista- 

 tum, and often mistaken for A. Goldianum. 



7. A. Goldianum, Ilook. Frond broadly ovate, or the fertile ovate- 

 oblong in outline (2-3° long) ; pinner (6-9' long), oblong-lanceolate, broad- 

 est in the middle, -pinnately parted; the dirisio7is {about 20 pairs) oblong-linear, 

 slightly scythe-shaped (9-15" long), serrate with appressed teeth; veins pin- 

 nately forking and bearing the fruit-dots very near the midvein ; indusium very 

 large, orbicular with a deep narrow sinus, smooth and without marginal 

 glands. — Rich and moist woods, from Conn, to Ky., and northward. July. 

 — A stately fern, often 4° high, the fronds growing in a circle from a stout 

 ascending chaffy rootstock, and decaying in autumn. Indusium with the 

 sides of the sinus often overlapping, thus appearing to be round and entire as 

 in § Polystichum. 



H-^-i-^-Zarr^e (1-3° high) ; stipes very chaffy at base; fronds twice pinnate, 

 but the upper pinnules confluent, some of the lower pinnatif d-toothed ; fruit- 

 dots rather large ; indusium convex, without marginal glands, persistent. 



8. A. Filix-mas, Swartz. Frond lanceolate in outline (1-3° high); 

 pinnae linear-lanceolate, tapering from base to apex ; pinnules oblong, very 

 obtuse, serrate at the apex and obscurely so at the sides, the basal incisely 

 lobed, distinct, the upper confluent ; fruit-dots nearer the midvein than the 

 margin, and usually confined to the lower half of each fertile pinnule. — 

 Rocky woods, N. Mich, to Dak. and Col. — Frond thickish but not surviving 

 the winter. (Eu.) 



9. A. marginale, Swartz. (PI. 19, fig. l, 2.) Frond evergreen, smooth, 

 thickish and almost coriaceous, ovate-oblong in outline (1-2° long); pinnae 

 lanceolate, acuminate, slightly broadest above the base ; pinnules oblong or 

 oblong-scythe-shaped, crowded, obtuse or pointed, entire or crenately-tootlied ; 

 fruit-dots close to the margin. — Rocky hillsides in rich woods; common, es- 

 pecially northward. Aug. 



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