ASPLENIUM. 
141 
cut away, tlie margin being either serrated or crenated. 
They are of leathery texture, but the veins are neverthe¬ 
less tolerably evident, each pinna having a midvein, from 
which veins are given off alternately on either side, these 
again producing a series of venules. The sori are pro¬ 
duced on the anterior side of each venule, lying obliquely, 
and forming two rows on each side the centre ; they are 
oblong or linear, covered by a persistent indusium, which 
opens along the anterior margin as the spore-cases grow 
towards maturity. 
The chief variation to which this Fern appears subject 
is that of the elongation of its parts. Sometimes the 
pinnae are much elongated, tapering to a narrow point; 
sometimes, besides being narrowed, they are auricled at the 
base, and deeply lobed. 
This species, with the Lanceolate Spleenwort and the 
Maidenhair, are exceedingly well adapted for Wardian 
cases in warm sitting-rooms. All of them enjoy the 
warmth; and being all evergreens of moderate size, and 
very elegant in structure, they supply just what is wanted 
in such situations. They should be planted on elevated 
rockwork, in sandy peat-soil lying in the interstices be¬ 
tween the fragments of stone ; and when once established 
