Aspidium . ] 
FERNS. 
39 
may add, my opinion also, that this plant is a variety of Filix-mas, though Sir 
William observes that Schkuhr, who found it near Dresden, looked upon it as a 
new species, and figured and described it as A. erosum. The continental A. Filix- 
mas is usually more crenate or serrate than ours. 
Sit. — Hedge-banks, &c., and in shady lanes throughout the kingdom. 
IIab. — I have received numerous habitats from most of the English and 
Scottish counties, from the extreme south to the Orkney Islands, and yet in some 
places this plant is rare. Inchnedamff, in Sutherland, is one of these — (3. Near 
Keswick, Cumberland, Mr. II. C. Watson. — y. Not very uncommon in dry 
situations in the south. — 8. Bomere Pool and Sutton Spa, both near Shrewsbury, 
Mr. W. Leighton. Nettlecomb, Somerset, Mr. W. C. Trevelyan. 
Geo. — North America, throughout Europe, and in Africa. 
7.— ASPIDIUM CRISTATUM. 
CRESTED SHIELD-FERN. 
(Plate III, fig. 4.) 
Ciia. — Frond pinnate. Pinnae opposite, pinnatifid, oblong, obtuse. 
Segments ovate, decurrent, crenate, bristled. 
Syn. — A spidium cristatum, Swz., Willd., Smith, Hook., Spreng., Gulp., 
Mack., Schk., Pursh. — Polypodium cristatum, Linn., Afzel in Stochh. 
Trans, for 1787. — (Not. oiBolt., With., or ILucls.) Polystichum crista- 
tum, Roth., Decan, Iloffm. — Polypodium callipteris, Ehrh., Hoffm . — 
Lastrrea cristata, Presl, Newm. 
Fig. — Hook., in Flo. Lon., new ser. 113. — E. B. 2125 (not 1949). — Newm. 
page 54. 
Des. — Root tufted. Fronds erect, rigid, yellowisli-green, bipin- 
nate, oblong, blunt. Pinnae opposite, eight to fourteen pairs, very 
distant (from each other, short, ovate, oblong, obtuse, very deeply 
pinnatifid or rather pinnate at their lower part. Segments ovate, 
crenate, each crenature furnished with two or three small sharp points 
or bristles, the principal vein in each segment slightly crooked, but 
the midrib of the whole pinna straight. Rachis slightly scaly only 
towards the lower part, where for about one third of its height it is 
otherwise naked. Sori large, very distinct, black at first, afterwards 
brown. Cover white when young, very thick, circular, with a 
lateral notch, and fixed by the centre. 
Few plants have occasioned more discussion than this. The difficulty has 
arisen chiefly because sufficient stress has not been laid upon the simply pinnate 
character of the frond; had this been regarded more, Aspidium spinulosum 
would not so often have been confounded with it. The cristatum, besides being 
less divided, has a more obtuse, more linear frond, and contracts very much, 
below. The sori of cristatum are comparatively much larger and less numerous 
and their covers persistent, not hidden by the capsules. It very nearly resembles 
the American Aspidium goldianum. 
Hab. — This is one of the rarest Ferns, not only here hut on the Continent. 
The only recorded habitats of it in this country, are the Lows, in Holt Heath, 
Norfolk,’ Rev. R. B. Francis. On hogs among alder hushes, at Westleton, 
