THE ALTERNATE-LEAVED SPLEENWORT. 127 
developed ; in small plants narrow-obovate or cuneate, cut into two 
or three narrow lobes, the lobes simple or toothed, the apex unequally 
toothed, the base tapering into a kind of petiole; in the larger 
specimens more distinctly stalked, and sometimes decidedly bipinnate 
with one distinct cuneate pinnule. The upper pinne become less 
lobed, but are unequally toothed at the apex, which is blunt, and 
they are falcately curved inwards. The apex of the frond consists 
of several coalescent smaller narrow lobes. 
Venation consisting of from two to four series of furcate divisions 
of the vein which constitutes the vascular bundle of the footstalk ; 
there is no costa or midvein, but one of the venules extends to each 
of the teeth, so that the pinnule is oceupied by from two to five or 
six flabellately-forked nearly parallel venules. i 
Fructification on the back of the frond, occupying all the pinne. 
Sori linear elongate, on two or three of the central venules, opening 
inwardly from each margin, at length confluent. Indusium a thin 
narrow membrane with the margin entire or somewhat wavy. Spore- 
cases obliquely obovate, brown. Spores roughish or muriculate, 
roundish-oblong. 
Duration. The caudex is perennial. The plant is evergreen or 
sub-evergreen, the fronds being more or less persistent 
This plant, though almost invariably kept distinct by writers on 
Ferns, has not unfrequently at the same time and by the same pen 
been marked as a dubious species, having a supposed relationship 
either to the Wall Rue, or the Forked Spleenwort. Without doubt 
it stands intermediate between these two Ferns, but it seems to us 
perfectly distinct from either of them. The subbipinnate variety 
of Wall Rue called cuneatum, is the only form which at all nearly 
resembles our present subject, and that is altogether a stouter more 
coriaceous plant, not lobed as this is, but toothed and having the 
apical teeth much more uniform. The Forked Spleenwort again is 
much more coriaceous and less leafy, its lobes being in truth rather 
rachiform than foliaceous, and its teeth, when present, very different, 
being rather like distant linear fragments split away from the margin, 
than serratures, which the few teeth of Asplenium germanicum more 

