WALL LETTUCE 



167 



grows on walls and rock ledges. It is found in the crevices of per- 

 pendicular faces of damp rocks in woods, well sheltered by overhanging 

 trees or vegetation, or on stony banks. It has an erect stem, with 

 peculiarly delicate leaves, with lobes larger upwards, runcinate, with 

 lobes each side of a common stalk, with a channelled leaf-stalk clasping 

 the stem, with angles and fine teeth, the terminal lobe the largest, five- 

 angled. The keel is smooth. 



The flowerheads are pale-yellow, and very small, having only 

 5 florets growing in erect 

 panicles, which are spread- 

 ing. The beak of the fruit 

 is shorter than the fruit. 



The plant is about 2 ft. 

 high. It is in bloom in 

 July. Perennial it can be 

 propagated by division, and 

 is really worth growing in 

 a garden. 



The flowerheads are 

 yellow, rather small and 

 distant, and the plant grows 

 in the shade, and is little 

 likely to be visited very 

 largely by insects. The 

 florets are few and herma- 

 phrodite. The stamens are 

 hair-like and short, and the 

 anthers, which are yellow, 

 form a cylinder. The style, 

 longer than the stamens, is 

 thread-like, with a stigma 



with 2 lobes, which is turned back. Thus the structure is quite 

 like that in most Composites, but self-pollination is more likely to 

 occur. 



The silky, simple, white pappus is light, and the achenes are 

 dispersed by the wind. 



Wall Lettuce is a rock plant growing on rock soil. The type of 

 rock varies, but is largely sandy, and not usually calcareous. Thus 

 it grows on Precambrian slate and on arenaceous marlstone of the 

 Middle Lias. 



The plant is infested by a fungus, Puccinia prenantkis. 



). H Crabtree 



WALL LETTUCE (Lactuca muralis, Gaertn.) 



