THE SPLEENWORTS. 



walls the finest specimens are always those which 

 are found at the top of the walls, just beneath the 

 coping-stone or crowning bricks, which serve as a 

 protection for the crown of the Wall Rue. Between 

 the bricks of walls and in the crevices of rocks the 

 little Fern inserts its wiry fibrous rootlets, which 

 suck in the moisture pent by the stony covering, 

 and revel in the combination of old mortar and 

 deposits of leaf -mould formed by dropping leaves. 

 The Wall Rue prefers to grow root-stock, crown, 

 and rootlets, horizontally, a position rendered 

 necessary by the habit of the little plant in gro wing- 

 between the mortar lines of walls. From its tufted 

 crown the tiny fronds shoot out in dense clusters. 

 Stem and leafy part are usually about equal in 

 length. The tiny branches of the frond are placed 

 alternately on each side of the rachis, each branch 

 being again divided into little diamond-shaped 

 lobes. These lobes are thick and leathery in tex- 

 ture and of a dark, shining green colour. When 

 the spores ripen the clusters of spore-cases 

 usually become confluent, so that in the autumn 

 the backs of the leaflets are thickly covered with 

 rich brown masses of seed. Evergreen in 



