ASPLENIUM. 
159 
peat, and limy rubbish. The pot, Mr. Johnson tells us, 
should be half filled with the rubbish ; then the earth 
should be put in and raised in the form of a cone, at the 
point of which the fern should be planted. The shelter 
of a bell-glass or cold frame is very desirable, but in this 
case care must be taken to admit the air freely from 
time to time. 
28 . Asplenium Ruta-muraria^ L, Wall Rue. 
Caudex short. Hoots abundant. Stems thickly tufted, half 
the length of the frond. Fronds pinnate. Leaflets broad at the 
top and tapering below into a winged footstalk, often twice or 
thrice divided, toothed. Yeins forked. Sori oblong. 
The caudex affects a somewhat creeping habit, extend- 
ing in the direction of the fissure of the rock, or the 
loosened mortar of the wall, 
amongst which its abundant 
matted roots make their home. 
The numerous stems are deep- 
ly tinted with dark purple or 
brown at the base ; they at- 
tain a height of from to 
3 inches, occupying half the 
length of the frond. The 
leaflets are few, leathery in 
texture, and of a dark glau- 
cous-green colour above and 
a paler shade below. When 
the involucres burst, the sori assume a chestnut colour, 
and often entirely cover the under part of the leaflets. 
This fern has its own peculiar beauty, forming neat, 
sober-looking tufts in the churchyard wall and upon the 
