Polypodium Dryopteris, Linnaeus. 
Gymnocarpium Dryopteris, Newman. 
OAK FERN. 
Roots — Radicles black and wiry: rbizome black, long, 
and creeping, much thinner than in the Polypodium 
Vulgare. 
Frond — Nearly triangular, three-branched; each branch 
pinnate, the pinnse opposite. 
Stipes — Twice the length of the frond, very slender, and 
smooth to the touch (especially when compared with the 
P. Galcareum ) ; there are a few straggling scales at the base. 
Pinnae — Opposite, pinnate at the base, and pinnatifid 
towards the end; apex sub-acute. 
Pinnules — Oblong, somewhat serrated, round at the 
apex; the basal pinnules are sessile. 
Venation — Midvein sinuous; lateral veins both simple 
and forked, extending to the margin. 
Fructification — Clusters of capsules marginal. 
Habitat — In moist shady places. Found near Rowsley, 
Ash over, &-c., on sandstone. 
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