»re divided rather more deeply than in the former. The 
ipper surface is a deep opaque green; and the under surface 
B densely covered with rust-coloured brown closely-packed 
overlapping scales, which, being just seen projecting from 
the margin, and still more fully in the exposed under surface 
of the young partially-developtd fronds, prettily contract \\ ith 
the deep green of the upper surface. The pinnae or lobes are 
mf an ovate form, and either entire or lobed on the margin. 
The opacity of the fronds renders the venation indistinct, 
and indeed it is only to be made out by examining young 
fronds, removing the covering of scales, and the outer skin 
of the frond itself It is then seen, that from the lower 
comer the principal vein enters, taking a sinuous course to¬ 
wards the upper side of the apex; it branches alternately, 
the venules being again branched, and the veinlets becoming 
joined more or less near the margin. The sori are borne 
along the sides of the venules in a very irregular manner, 
the majority of them being directed towards the apex of the 
pinna. At first, the sori are quite concealed by the scales, 
but the spore-cases ultimately protrude between them. 
The CeLerach is a mural species, occurring on the walls of 
old buildings and ruins, and in rocky places. It is pretty 
generally distributed in the United Kin gdom, but is consi¬ 
dered somewhat rare in Scotland. It occurs also throughout 
central and southern Europe, and in the north of Africa. 
Like other wall Ferns, this is often difficult to establish 
when once this is ; 
Tms plant is referred by some authors to Blecknum, and by 
others to Lamaria. We think it most nearly related to the 
former, although in the contraction of its fertile fronds it 
undoubtedly resembles the latter. Among the British Ferns 
tiie only species of this genus is known by having its fruetd- 
M&aon extended longitudinally on the pinnae, so as to form 
a linear or continuous sorus on each side the midvein, and 
•bout midway between it and the margin. No other British 
