286 THE FERN PARADISE. 



present. It delights in the spray of waterfalls, 

 or to be perched on the damp rocks round which 

 the mountain streams rush and roar. In such 

 situations it has a wide distribution throughout 

 the United Kingdom. The fronds grow from little 

 black, wire-like rhizomes, which often become 

 densely interlaced with the mosses which grow 

 on boulder-tops in mid-stream, or wherever per- 

 petual moisture makes moss life predominant. 

 They have short wire-like stems, and the leafy 

 or filmy portion consists of a series of branched 

 veins arranged alternately on each side of the 

 rachis. The primary veins are divided into 

 veinlets, which are arranged in pairs on each 

 side of the primary veins. Each vein, whether 

 primary or secondary, is bordered by a narrow, 

 filmy, leafy wing. The seeds, when they are 

 formed, are placed in little cup-shaped receptacles 

 in the angles made by the rachis and the 

 primary branches of the frond. The general out- 

 line of the latter is somewhat egg-shaped. The 

 leafy filaments are of a dull, brownish-green 

 colour, and semi-transparent 



