144 HISTORY OP BRITISH FERNS. 



into spore- cases sometimes a few pinnae at the middle of 

 the frond, while the apex is leafy, sometimes the base of 

 a pinna., while its apex retains the leafy form, sometimes the 

 base of a pinnule here and there, just its apex too, being 

 broad and leafy ; but the usual condition is to find a few 

 of the shortened pinnse, which form the apex of the frond, 

 contracted and soriferous throughout. 



The venation, as seen in the barren fronds, consists of 

 a prominent midvein, bearing once or twice forked venules 

 proceeding to the margin in direct lines. In the fertile 

 parts of the frond, only the midrib of the pinnules is fully 

 developed, and the spore-cases are attached to a small por- 

 tion of the venules which becomes developed just to serve 

 as a receptacle. The spore-cases are subglobose, shortly 

 stalked, reticulated, and two-valved, opening vertically. 



The Osmund Eoyal is a widely-distributed plant, oc- 

 curring in favourable localities, that is, marshy and boggy 

 situations, throughout the United Kingdom, and, as already 

 mentioned, extremely abundant and luxuriant in some parts 

 of Ireland. It is common throughout Europe, and occurs 

 in the United States of America. 



This plant is especially suited, in cultivation, to occupy the 

 base of rock-work abutting upon a piece of water, where its 



