PERNS OF GREAT BRITAIN. 63 



species. It is a smaller plant, its pinnae being more 

 horizontal in form, and all its parts more blunt. Its 

 veining is similar, but tbe fructification is at the ter- 

 mination and not near the middle of the secondary vein, 

 and is thus more distinctly marginal. The clusters are 

 at first separate, but as they ripen they run into a mass, 

 and form a brown ridge on the under surface of the 

 pinnules. This constitutes a very marked difference 

 between this and the Brittle Bladder-fern. The smooth 

 slender rachis is almost always of a brownish purple 

 colour. 



This Toothed Bladder-fern is not uncommon in the 

 North of England, as about Settle, in Yorkshire, at 

 Cauldron Snout, Dm'ham, and various other localities. 

 It is found, too, near Matlock Baths, on the Cheddar 

 Chffs, at Tunbridge Wells, and numerous other spots 

 throughout the kingdom where the soil is rocky, though 

 it is probably often overlooked and mistaken for Cysto- 

 pteris frdgilis. 



A most marked variety of this fern, termed Biclcie- 

 ana, has a very compact frond, and is a very beautiful 

 plant, of a deep green colour, and almost transparent 

 texture. The general outline is nearly egg-shaped, but 

 terminating in a point, and the pinnae are egg-shaped 

 and lanceolate, overlapping each other, the pinnules 

 running closely together so as to form a wing. They 

 are broad and blunt, with a few shallow marginal 

 notches, and the fructification is also marginal. Dr. 

 Dickie discovered this remarkable variety in 1846. 

 He found it growing in a sea-cave near Aberdeen. No 

 other native locality of this plant is recorded, but it is 



