PTERIS. 



green ; revolute at the margin, which is brownish, and slightly crisped 

 or wavy, sheltering the dense linear masses of tawny thecae. Barren 

 leaflets pale and hairy at the back. The main stalk is angular and 

 sharp-edged, wounding the hands severely if plucked incautiously. 

 When cut across, the rhizoma has a branched appearance, resembling a 

 spread-eagle, whence the Latin name. Smith. Rhizoma astringent 

 and said to be anthelmintic. It has been used, and with some success, 

 as a substitute for hops. In the Canaries a miserable sort of bread 

 is made by mixing the flour obtained by grinding the rhizoma, with 

 barley meal. 



NEPHRODIUM. 



Thecae placed in the middle of a vein, forming roundish sori 

 placed in rows. Indusium reniform. 



1318. N. Filix mas Presl. Aspidium Filix mas Swartz. 

 syn. 55. E. Bot. t. 1558. Smith Eng. Fl. iv. 288. Polypo- 

 dium filix mas Linn. sp. pi. 1551. All over the North of 

 Europe. 



Rhizoma tufted, large, scaly. Leaves several, 3 feet high, erect, 

 disposed in a circle, lanceolate, and leafy nearly to the bottom ; their 

 stalks and midribs scaly, or chaffy, throughout ; divisions alternate, 

 taper-pointed, pinnate ; leaflets numerous, crowded, sessile, for the 

 most part distinct, occasionally somewhat combined at the base, oblong, 

 obtuse, crenate throughout, the lateral notches broadest and most 

 shallow, the terminal ones more crowded and acute, without any termi- 

 nal bristles ; both sides smooth, and destitute of glandular globules, but 

 there is a depression on the upper one, over the insertion of each sorus. 

 Sori circular, tawny, ranged in simple, close, short rows, near the 

 partial midrib, and scarcely occupying more than the lower half of each 

 leaflet. Indusium circular, durable, crenate, tumid, with a cleft termi- 

 nating in the central depression. Thecae numerous, shining-brown, 

 prominent all round for a little beyond the indusium. Smith. 

 Rhizoma used as an anthelmintic. The oil of Fern, extracted by ether, 

 is the most efficacious form in which it is administered. 



OSMUNDA. 



Thecae collected into a panicle, or along the edge of the al- 

 tered frond, opening vertically, bound by a broad dorsal wing. 



1319. O.regalis Linn, sp.pl. 1521. Eng. Bot. t. 209. Smith 

 Eng. Fl. iv. 327. Bogs, woods and wet meadows in Europe. 

 (Osmund Royal.) 



Rhizoma tuberous, hard, scaly, beset with numerous fibres, and 

 having in the centre a whitish core. Leaves several, erect, 2 or 3 feet 

 high, doubly pinnate, smooth, bright-green ; the primary divisions from 

 6 to 10, nearly opposite, hardly a span long ; leaflets more numerous, 

 often decidedly alternate, sessile, or nearly so, oblong, bluntish, entire, 

 or obscurely crenate with 1 rib, and numerous transverse veins ; the 

 base dilated, heart-shaped, or somewhat lobed. Some of the upper 

 619 



