THE FILMY FERNS. 



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 

 usually 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 outline of the latter is somewhat egg- 

 shaped. The leafy filaments are of a dull, 

 brownish-green colour, and semi-transparent. 



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