Plants 3 dm. or higher; the divisions of the ternate 
leaf 2-pinnatifid; pinnae sessile or nearly so; segments 
rounded. 
Stony Man Mountain, Va., W. Palmer and King. 
8. PTERIDIUI1 Scopoli, 1760. 
Lhe name Pteridion was applied by Valer. Cordus 
[Hist. de Plantis 2: 170. 1561.] to Phegopteris dryo- 
Bpteris, The ancient name for the Eagle Fern was 
without doubt Thelypteris. 
Rootstock creeping, blackish. Leaves usually ternate. 
Sporecases borne in sori upon a revolute portion of the 
leaf-margin. Indusium membranous. 
1. P. aquilinum (L.) Kuhn. 
Lilix foemina, foliis per margines pulverulen- 
tes. . Banister; Ray, Hist. 2: 1928. 
Pteris fronde supradecomposita . . Gron.F\. 2: 
197. 
Plevs aguilina L. Sp. Pl. 1075. Haton, Ferns 1: 
263. t. 35; in Gray Man. 681. Underw. in Il. 
Fl. 1: 28. Clute, Ferns 69. Waters Ferns 93. 
Pteridium aquilinum Kuhn, 1879. in Decken’s 
Reis. 3: 11. Underw. Nat. Ferns 91; in Britt. 
Man. 8. 
EAGLE Fern, Bracken. 
Plants 5-20 dm. or higher; leaves ovate-triangular or 
ternate 2-3-pinnate at the base; pinnules lobed or entire. 
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