on British Ferns. xxix 



Ohs. — Tliis genus is indicated by Presl under the title of Polypodi- 

 um § Cteuopteris, but I am not sufficiently acquainted with the host 

 of exotic species which that author has placed in his sectional divisions 

 to express any opuiiou as to their affinity. The genus, as restricted 

 above, is sufficiently extensive, and has not, as far as my information 

 • extends, been previously isolated. 



Ctenopteris vulgaris. 



Pol}T3odium vulgare, Linn. Sp. PI. 1544; Light/. Fl. Scot. 



667; Huds. Fl. Ang. 455; With. Arr. 773; Sm. E.F. 



iv. 280, E. B. 1149 ; Mack. Fl. Hib. 337 ; Newm. N. 



A. 13, F. Ill ; Hook, and Am. 566 ; Bab. 408. 

 Polipodium vulgare, Bolt. Fit Brit. 32, t. 18. 

 Polypodium Ctenopteris vulgare, Presl, Tent. Pteridog. 179. 



Stipes articulated at the base, of nearly equal length with 

 the fi'ond ; frond pinnatifid. 



Walls, trees and hedge-banks, common. 



Obs. — The Polypodium cambricum of all authors is refenible to this 

 species. 



Obs. — The beautiful Davallia canariensis, which, together with the ex- 

 tensive family to which it belongs, is intermediate between Polypodiese 

 and HymenophyUese, may possibly occur in the South-west of Ireland. 



Family. — HYMENOPHYiiLE^. 



Frond appearing to consist of branched veins, each ac- 

 companied throughout by a membranous wing or margin : 

 cluster of capsules nearly spherical, seated on one of these 

 veins which projects beyond the edge of the leaf, the clus- 

 ter being inclosed in a kind of cup-like involucre. 



Genus. — Trichoivianes, Linneus. 



Involucre elongate, somewhat urn-shaped : capsuliferous 

 vein projecting beyond it in the form of along stiff bristle. 



Trichomanes speciosum. 



Trichomanes speciosum, Willd. Sp. PI. v. 514 ; Newm. N. 



A. 29, F. 305. 

 Trichomanes brevisetum, R. Br. in Ait. Hort. Kew. v. 529 ; 

 Sm. E. F. iv. 324 ; Mack. Fl. Hib. 344. 



