WOODSIAS. 



101 



cover fall back, and appear like a fringe around tlie base 

 of the clusters of spores. A covering of this nature is 

 not present in any other group of British ferns, and is 

 sufficient for its discrimination. Ttie leaf-stalks are 

 jointed at a short distance from the root-stock, and at 

 this joint or articulation the old fronds separate from the 

 stock — a peculiarity confined to the Woodsias amongst 

 British ferns. 



The two British species of "Woodsia may be distin- 

 guished by the following characters : 



Alpine "Woodsia. — Fronds narrow, nearly smooth, 

 leaflets almost triangular; 



Hairy Woodsia. — Fronds spear-shaped, hairy leaflets, 

 oblong. 



ALPINE WOODSIA.^ 



This little Woodsia grows in tufts seldom more than 

 2 or 3 inches in height, and naturally in almost inac- 

 cessible places. The outline of the fronds is 

 narrowly spear-shaped, almost strap-shaped. 

 They consist of a stalk bearing on each the 

 somewhat bluntly triangular leaflets: these 

 leaflets have a distance between them equal 

 to the width of a leaflet, and they do not 

 stand exactly opposite to each other in their 

 arrangement up the stalk. The leaflets are 

 closer together at the top than at the bottom 

 of the fronds. This species is scarcely hairy ; 

 it is indeed smooth as compared with its 

 fellow, the Hairy Woodsia. A few scaly 

 hairs are sprinkled over the surface of the 

 fronds, but these are more resembling scales 

 than hairs. The tufts of spore-cases are pro- 

 duced freely on the backs of the leaflets. 

 Surrounded by the fringed edge of the rup- 

 tured covering, they present an appearance 

 sufficiently distinct for the identification of the genus. 



* Woodsi hyberborea, R. Br. 



