WOODSIA ILVENSIS. 
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WOO'DSIA ILVE'NSIS. 
This Fern has been included by various botanists in 
the genera Acrostiohum, Lonchitis, and Polypodium; 
but they have uniformly retained the specific name 
Ilvensis, which is one of the illustrations of the absurdity 
of naming a plant after the country where it was first 
found. Ilvensis, or Elban, refers to the Isle of Elba, 
where it was originally discovered; but since then it has 
been found in Britain, all over Germany, the Alps, the 
Pyrenees, Siberia, and even Greenland. The true render¬ 
ing of the botanical name, then, is the Elban Woodsia; 
but it has also been called Oblong Woodsia, Hairy 
Woodsia, Downy Hair Fern, and Opposite-leaved Poly¬ 
pody. 
Roots tufted, numerous, long, smooth, blackish, fibrous. 
Fronds several, in a tuft or group, erect, spear-head 
shaped in general outline, from two to five inches high. 
Stem pale brown, slightly scaly, very elastic and wiry, 
about one-fourth without leaflets, and jointed at a short 
distance from the roots. At that joint it falls off when 
decayed. Leaflets stalkless, egg-shaped, bluntly-pointed, 
deeply out into segments, somewhat wavy, and rolled 
tack at the edge; opposite at the lowest part of the 
frond, but alternate at the top; upper surface milky 
green, smooth, but sprinkled over with a few hairs or 
lender scales; under surface densely covered with 
similarly fine, glossy scales and jointed hairs, and nearly 
covered with fructification. Fructification in round, 
