lo]- 



riLicES. 623 



(Fmctiflcation concealed by, or intermixed with, chaffy scales or hairs .... 9 

 Fructification in lines along the margin of the fronds, the indusium a membrane 

 attached to the raarg;iu 10 

 Fructification in circular, oblong, or linear aori, on the under surface, without chafiy 

 scales 11 



fFronds deeply pinnatifid, with entire segments. Sori linear, concealed by the scales. 

 . ) 10. Cetebach. 



I Fronds twice pinnate, with small segments. Sori circular, with chaffy hairs intermixed. 

 (^ 15. AVOODSIA. 



fTaU, erect, stiff fern, ternately divided, with pinnate branches and sessile lobes. 



12. Pteeis. 

 Delicate fern, not a foot high, much divided, with broad, wedge-shaped lobes on ca- 



(.. piUary stalks 13. Adiant. 



rSori oblong or Unear, covered (when young) with a membrane attached along the 



1 1 J side 12 



1 Sori circular, either without any indusium, or covered (when young) with a mem- 



[^ brane attached by the centre or by a lateral point 13 



rFrond entire. Indusium opening in a sUt along the centre . .9. Haet's-tongue. 

 12'j Frond pinnate or much divided. Indusium opening along the inner side. 



l^ 8. Spleentvoet. 



("Fronds simply pinnate, with entire or toothed segments or pinnaa 14 



13 < Fronds pinnate, with pinnatifid primary divisions or pinnas, or twice or thrice pin- 



(. nate* 15 



['Segments narrow-lanceolate, rather thick, attached to the stalk by a broad base, and 

 confluent. Sori golden-yellow, mthout any indusium 4 (1). Common Polypody. 

 Segments distinct or stalked, ovate-falcate, prickly-toothed, with a prominent angle 

 14-i or lobe at the base on the inner side. Sori witha small, circular indusium. 



7(1). Soil!/ Shieldfeen. 

 I Segments small, obovate. Stalk black and slender. Indusium attached laterally. 

 \. 8 (5). Common Spleenwoet. 

 rLower pair of pinnas much larger than the others, giving the frond a broadly trian- 

 gular or rhomboidal form 16 



Lowest pair, or several lower pairs of pinnas, decreasing in size or not larger than the 



l^ rest. Frond ovate or lanceolate in outline 17 



['Fronds once pinnate, with pinnatifid segments 4 (2). JSeecA Polypody. 



16-! Fronds twice pinnate, the pinnas mostly opposite . . , .4(4). Oai: Polypody. 



^Fronds twice pinnate, the pinnas mostly alternate 14. Bladdeefeeh. 



['Fronds delicate, seldom a foot high, without any brown scarious scales (or very few 



at the base of the stalk), twice pinnate, with stalked pinnas 18 



17-^ Fronds stiff, 1 to 3 feet high or more (except in the Beech Polypody). The stalk more 

 I or leas shaggy below the leafy part, with brown scarious scales (except in the Marsh 



( Shieldfern) 19 



['Segments with fine pointed teeth 8. SpleenwobTw 



Segments oblong or lanceolate, nearly sessile, with obtuse teeth or lobes. 

 18-{ 14. Bladdeefbeit. 



t Segments small, obovate, stalked, with obtuse teeth. Delicate annual. 

 6. Gymnogeam. 

 rFronds pinnate, the pinnas deeply pinnatifid, the lobes entire or obtuse, and slightly 



19.| toothed 20 



(^Fronds twice pinnate, the segments sharply toothed or pinnatifid 24 



(■Piunas (all but the lowest pair) attached to the stalk by their broad base. 

 20^ 4 (2). Beech Poly50dt. 

 (, Pinnas attached by their midrib only 21 



isL 



„, f Lobes of thcjji^mas^ntire. Sori near their margins 22 



J^ Lobes of thefl»»^ightly toothed. Sori near their base or centre 23 



C No scarious scales ou the stalk. No glands on the leafy part. 

 2,1 7 (3). IfursA Shield feen. 



I Stalk with brown scarious scales at the base. Minute glands on the under surface of 



I. the segments 7 (4). J/oiiHteJji Shieldfeen. 



("Segments of the pinnas oblong, very numerous, scarcely broader at tlie liase. 

 23-J 7 (5). Male Shieldfeen. 



(^Segments ovate, wedge-shaped at the base 7(6). Cres<e(Z Shieldfeen. 



/"Segments of the pinnas with finely-pointed, almost prickly teeth; the inner lobe or 

 0,3 tooth at the base much larger than the rest . . . .7(2). PricWj^ Shieldfeen. 

 " i Segments of the pinnas with shortly pointed teeth or pinnatifid ; the lobes of each 



(. side similar 25 



" In all twice or thrice pinnate leaves or fronds the primary divisions on each side of 

 the main stalk are called ^umas, the ultimate divisions retaining the name of tegmentt. 



I 



