Polypodium Dryopteris, Linneews. 
Gymnocarpium Dryopteris, Newman. 
OAK FERN. 
Roots — Radicles black and wiry : rhizome black, long, 
and creeping, much thinner than in the Polypodium 
Vulgave. 
Frond —Nearly triangular, three-branched; each branch 
pinnate, the pinnae opposite. 
Stipes — Twice the length of the frond, very slender, and 
smooth to the touch (especially when compared with the 
P. Calcar cum) ; 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 — Mid vein sinuous; lateral veins both simple 
and forked, extending to the margin. 
Fructification — Clusters of capsules marginal. 
Habitat — In moist shady places. F ound near Rowsley, 
Ash over, &c., on sandstone. 
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