odorous after several years. When
growing the fern may be tested "by its fragrance, its stickiness and its
beautiful brown curls." Evergreen. Spores ripen the middle of August.

[Illustration: Fragrant Fern. _Aspidium fragrans_ (Mt. Mansfield. Vt.)]

KEY TO THE WOOD FERNS

ASPIDIUM

Fronds pinnate, the pinnae pinnatifid;
Blade soft and thin, not evergreen;
Lower pinnae reduced to mere lobes
New York Fern
Lower pinnae but slightly reduced;
Veins simple......................Massachusetts Fern
Veins forked..............................Marsh Fern

Blade rather thick (subcoreaceous) mostly evergreen;
Fronds small, narrow, glandular, rock species
Fragrant Fern
Fronds large, two or more feet high;
Lower pinnae short, broadly triangular
Crested Shield Fern
Lower pinnae longer;
Sori close to the margin.... Marginal Shield Fern
Sori nearer the midvein;
Frond lanceolate....................Male Fern
Frond ovate..............Goldie's Shield Fern

Fronds twice pinnate with the lower pinnules pinnatifid
Boott's Shield Fern

Fronds nearly thrice pinnate................Spinulose Shield Fern

[Illustration: Marginal Shield Fern. _Aspidium marginale_]

THE WOOD FERNS

The ferns of this group, not counting the small fragrant fern, prefer the
woods or at least shady places. Although the genus _Polystichum_ represents
the true shield ferns, the wood ferns are also thus designated, as their
indusia have nearly the shape of small, roundish shields. The old generic
name for them all was _Aspidium_ (meaning shield), first published in 1800.
For a long time its chief rival was _Nephrodium_ (kidney-like), 1803. Many
modern botanists have preferred the earlier name _Dryopteris_ (1763),
meaning oak fern, alluding, perhaps, to its forest-loving habits.
THELYPTERIS, still earlier (1762), may supersede the others.

[Illustration: Marginal Shield Fern. Aspidium marginale (From Woolson's
"Ferns," Doubleday, Page & Co.)]

[Illustration: Sori of Marginal Shield Fern]

(1) MARGINAL SHIELD FERN, EVERGREEN WOOD FERN

_Aspidium marginale_. THELYPTERIS MARGINALIS
_Dryopteris margina