280 CRYPTOGAMIA— FILICES. Polypodium. 



described. The membranous cover, or involucrum, which 

 protects the masses of ca])sules till they arrive at maturity, 

 originates either from the surface of the frond^ when it 

 is termed superficial ; or terminates a rib, vein, or seg- 

 ment; or is laterally inserted, by one of its margins, 

 into a vein or rib, the opposite margin being closely 

 pressed, if not in any degree attached, to the cuticle of 

 the leaf- 

 It is remarkable that insects scarcely ever feed on dried 

 specimens of Ferns. 



463. POLYPODIUM. Polypody. 



Linw. Gen. 560, Jmss. 15. Fl.Br.WXZ. Sm.in Act. Taunn.v.5. 

 408. Tracts 23 1 . sect. 1 . Swartz Syn. Fil. 25. Br. Prodr. 146. 

 Tourn. t.3l6. Lam. t. 866. 



Nat. Ord. Filices. Linn. 55. Juss. 5. Br. Prodr. 14.5. 



Masses of capsules nearly orbicular, convex, scattered over 

 the back of the frond^ in rows, between the midrib of 

 each lobe and the margin, without any membranous 

 cover. Capsules .very numerous, globose, on capillary 

 stalks ; each of 1 cell, and 2 equal, hemispherical valves, 

 bound together by a transverse, jointed ring, which finally, 

 when dry, separates them by its elasticity. Seeds nume- 

 rous, roundish, very minute. 



Herbaceous, or perhaps arborescent. Root creeping, often 

 scaly. Fronds erect, simple or variously pinnate, more 

 or less compound ; undivided, or mostly pinnatifid ; en- 

 tire or serrated; of a firm texture, generally smooth. 

 Caps, tawny. Natives of almost every climate. 



* Frond pinnatifid. 



1. P. vulgare. Common Polypody. 



Frond deeply pinnatifid ; lobes oblong, somewhat serrated, 

 obtuse. Root scaly. 



P. vulgare. Linn. Sp. PL 1544. Willd. v. 5. 172. Fl. Br. 1113. 



Engl. Bot. V. \6.t.\ 149. Hook. Scot. p. 2. 153. Curt. Lond. 



fast:. 1 . t. 68. Woodv. suppl. t.27\. Bolt. Fil. 32. t. 18. Fl. Dan. 



i. lOGO. Bull. Fr. t. 191. Ehrh. Crypt. 121. Bauh. Pin.359. 



Plum.Fil.pref.27.t.A.f.2. Moris.v. 3. 562. sect. 14. t. 2. f. I. 

 P. n. 1696. Hall. Hist. V. 3. II. 

 Polypodium. Rail Syn. 117, Ger. Em. 1 1 32./, 1 , 2, Trag. Hist. 



