56 HISTORY OF BRITISH FERNS. 



5. P. alpestre, Sprengel. — Fronds bipinnate, lanceolate. 

 Plate XXL 

 tar. flexile. — Fronds narro-n', flaccid ; pinnre deflexcd. 



Genus 2. ALLOSORUS, Bernhardi. 



1. A. crispiis, Bernhardi. — The onl_y British species. Plate 

 V. % 1. 



POLYPODIACEiE § GyMNOGRAMME.E, 



Genus ^. GYM NOG RAM MA, Desmu.v. 



1. G. leptophylla, -Z?^sf«?;A% — The only British species. 

 Plate XXII. fig. 1. 



POLYPODIACEiE § ASPIDIE.E. 



Genus ^. POLYSTICHUM, i?Oi;/^ 



1. P. Lonchitis, Both. — Fronds pinnate, spiny- serrate. 



Plate IV. fig. 2. 



2. P. aculeatum, Both. — Frond bipinnate, rigid, pinnules 



ovate-STibfalcate, auricled, acute, acutely wedge-shaped 

 at the base, nearly all distinct. 

 tar. lobatum. — Fronds narrower, pinnules nearly all 



decurrent. Plate IV. fig. S. 



