on British Ferns. xxi 



Rhizoma tufted ; stipes short, densely clothed with red- 

 dish scales ; fronds semi-erect, lanceolate, pinnate ; pinnse 

 numerous, pinnate ; pinnules blunt, serrated; involucre ve- 

 ry perfect, without stalked glands; clusters of capsules less 

 crowded nearer the midrib, absent from the lower pinnse. 



Common everywhere, 



Ohs. — Two appai-ent species, when better understood, may be intro- 

 duced here, Lophodium erosum, the Aspidium erosum of Schkuhr, 

 and L. abbreviatum, the Polystichum abbreviatum of Decandolle. 



Lophodium (rigidum) pragrans. 



1753. Polypodium fragrans, Linn. Sp. PI 1089, (1st edi- 

 tion) ; Hiids. Fl. Ang. 388, (1st edition) ; With. Arr. 

 650 ; Villars, Hist. PI. Dauph. iii. 843. 

 1795. Polypodium rigidum, Hoffm. Deutsch. Flor. ii. 16. 

 1810. Polystichum strigosum, Roth, Fl. Germ. iii. 86. 

 Aspidium fragi'ans. Gray, Nat. Arr. ii. 9. 

 Aspidium rigidum {Swartz), Hook, E. B. S. 2724 ; Hook. 



and Am. 569. * 



Lastrea rigida {Presl), Newm. N. A. 19, F. 191 ; Bah. 411. 

 Ehizoma tufted; stipes much shorter than the frond, 

 densely clothed with reddish scales ; frond semi-erect, 

 glandulose, sweet-scented, lanceolate, pinnate ; pinnae very 

 numerous; pinnules oblong, obtuse, serrated; involucre 

 very perfect, fringed with stalked glands ; clusters of cap- 

 sules very crowded, covering the pinnules, absent from the 

 lower pinnse. 



Not uncommon upon limestone rocks in the North of 

 England. 



Genus. — Hemestheum. 



Clusters of capsules on both branches of the lateral 

 veins, and equidistant from the mid-vein, so as to form a 

 continuous submarginal series, which, in the first division, 

 is completely covered by the revolute margin of the pin- 

 nule ; in the second division, nearly so : involucre insta- 

 ble, sometimes totally absent, at other times small, indis- 

 tinct, subreniform, evanescent : first upper pinnule longer 



