riLiOES. 625 



In dry, liilly, or mountain pastures, in northern and Arctic Europe, 

 Asia, and America, in tlie mountains of central and southern Europe, the 

 Caucasus, and Altai, and reappearing in the Antarctic regions. Widely 

 diffused over Britain, but not generally common. Fr. summer. 



III. OSMUND. OSMUNDA. 



Fronds once or twice pinnate, the leafy part barren ; the fructification 

 consisting of clustered spore-cases, either in a panicle at the end of the 

 frond, or, in exotic species, in some other part of the frond, but always dis- 

 tinct from the leaf-like part ; each spore-case opening by a vertical fissure. 



A genus of few species, natives chiefly of the temperate regions of both 

 hemispheres, especially the northern one. 



1. Royal Osmund. Osmunda recalls, Linn. 

 (Eng. Bot. t. 209.) 



The perennial stock often forms a trunk rising perceptibly from the 

 ground, and sometimes to the height of a foot or more. Fronds growing in 

 tufts, erect, from a foot or two in dry, poor soils, to 8 or 10 feet when very 

 luxuriant, twice pinnate, with lanceolate or oblong segments, 1 to 2 inches 

 long, rather stiff, prominently veined, either entire or obscurely crenate. 

 Fructification forming a more or less compound panicle at the top of the 

 frond, usually bipinnate, each spike-hke branch representing a segment of 

 the frond. 



In moist or boggy places, in western, central, and some parts of southern 

 and south-eastern Europe, extending northwards to southern Scandinavia ; 

 also in central Asia, North and South America, and southern Africa. In 

 Britain, chiefly in the western counties of England and Scotland, in Wales, 

 and Ireland, apparently very local in other parts of England, and entirely 

 absent from several counties. Fr. end of summer, or autumn. 



IV. POLYPODY. POLYPODIUM. 



Fronds (in the British species) either pinnate or temately divided, with 

 the branches pmnate. Spore-cases minute, coUected in circular clusters or 

 sori on the under side of the segments, without any indusium or involucre ; 

 each spore-case (as in aU the foUowing genera) encircled by an elastic jointed 

 ring, and bursting irregidarly on one side, having then, under a microscope, 

 the appearance of a little helmet. 



A large genus, widely distributed over the globe, only differing froni 

 Aspidium in the absence of any indusium or membrane covering the sori 

 even when voung. For the Table of Species, see the Generic Table above, 

 p. 623, n. 13. 



1. Common Polypody. Poljrpodium vnlgare, Linn. 

 (Eng. Bot. t. 1149.) 

 Kootstock thick, woody, and creepuig. Fronds about 6 inches to a foot 

 high, of a firm consistence, without any scales on then- stalk, broadly oblong- 

 lanceolate or somewhat ovate in their general outline, simply pmnate or 



3h 



