THE COMMON POLYPODY. 83 



Rootstock, a hairy or scaly rhizoma, which branches and 

 creeps in various directions upon the surface of the rock, 

 wall, or soil in which the plant is growing, producing 

 fronds from numerous points of its upper side. Fronds 

 evergreen, numerous, deeply pinnatifid, of a somewhat 

 elongated egg-shape, pointed at the apex, and divided 

 into long, blunt-pointed, entire pinnae, an inch or more 

 in length each resembling somewhat the finger of the 

 hand with deep wide clefts between each. Stipes of 

 varying length, green, smooth, brittle, sometimes as long 

 as, sometimes shorter than, and often much longer than, 

 the leafy part. Fructification usually confined to the 

 upper portion of the undersides of the pinnae, consisting 

 of two rows of non-indusiate, rounded sori, one on each 

 side of the midvein of each pinna, generally crowded, 

 and sometimes becoming confluent. When ripened, the 

 sporangia turn to a rich orange, or brown, colour. 



HABITATS. The tops and sides of rocks and walls. It 

 is especially luxuriant where moist seams of earth, lying 

 in shaded positions, afford abundant root-room, and it is 

 oftentimes much stunted and diminutive on the drier, 

 exposed, and sunny faces of rocks and walls. Old walls 

 falling into ruin are always found to have accumulated 

 soil between their loose stones. Should trees be growing 

 around, this accretion of soil will be largely composed 

 of leaf-mould, and upon the shadowy sides of such walls 

 all rock or wall-growing ferns will be found in the 

 greatest state of vigour and luxuriance. The Common 

 Polypody grows also in the forks of old trees where leaf- 

 mould has accumulated; upon tree-stumps raised above, 

 or almost level with, the ground; in the sides and upon 

 the tops of hedgebanks, amongst loose stones, or in the 

 stumps, trunks, forks, or hollows of trees growing 

 in hedgebanks. Pollard-trees in hedgebanks afford 

 favourite habitats of this fern. Old bridge-arches, and 

 indeed all old or decaying stonework, are, similarly, 

 favourable positions for Polypodium vulgare. Wherever, 



