EQUISETACEiE. 



423 



more marked at the base of the teeth, p. 7, 8. 



Wet shady hanks. Rare. 



9. trachyodon. Stems simple, with 7- 

 11 furrows. Sheaths lax: their Ribs flat. 

 Teeth ovate, obtuse, muriculate on back and 

 margin, with a brown excurrent dorsal line. 

 p. Summer. Moist sandy. Rhine. 



10. niackaii. Stem simple or slightly 

 branched, with 8-12 furrows. Teeth slender. 



persistent, at last Hack. 

 dorsal depression, p. 7, f 

 Belfast. Sc. 



Ribs with a deep 



. Mountain glens. 



11. variegatum. Stem slightly branched, 

 rough, with 5-9 fiuTOWs. Sheaths green at 

 base. Teeth obtuse, each tipped with a de- 

 cided bristle, black in the middle, with a white 

 membranous margin. Ribs with a deep dorsal 

 depression, p. 7, 8. Barren, wet. Br. G. Sw. 



CXVI. FILICES. 



Tribe I. POLTPOmUJE. 



918. POLYPODKJM. 



1. vulgare. Frond deeply pinnatifid. Lobes 

 oblong, crenulate. Stem scaly, p. 8-10. Walls, 

 banks, and old trees. 



j8. serratum. Lobes lineari-Ianceolate, serrate. 

 7. camhricum. Lobes pinnatitid. 



2. Phegopteris. Frond pinnate. Pinnaj 

 lineai-i-lanceolate, united at base; lower tmiied 

 downwards. Lobes lanceolate, obtuse, entire. 

 Son marginal, p. 7-9. Bogs and damp 

 among mountains. 



3. rhseticum. Frond smooth, oblongo- 

 lanceolate, bipinnate. Pinnules pinnatipartite. 

 Segm. inciso-crenate, obliquely mucronate. p. 

 7, 8. 2Iountain thickets. Hartz. Vosges. Alps. 

 Habit of Athyrium Filix-foemina. 



4. Dryopteris. Frond temate, vrithout 

 glands. Div. pinnate. Pinnte pinnatifid, ob- 

 tuse ; uppermost neai'ly entire. Sori marginal. 

 p. 7. Bocky mountains. 



5. calcareum. Frond ternate ; with stalk- 

 ed glands. Div. pinnate. Pinnse pinnatifid, 

 obtuse ; uppermost nearly entire. Sori mar- 

 ginal, p. 7. Rocky calc. 



919. POLYSTICHUM. 



1. Zjoncliitis. Frond lineari-Ianceolate, 

 pinnate. Pinnae sessile, lunulato-triangular, 

 spinuloso-serrate, rigid, p. 7. High rocks. 



2. aculeatum. Frond (when fuUy deve- 

 loped) oblongo-lanceolate, bipinnate. Pinnules 

 ovato-lunulate, decun-ent. p. 7- Shady rocks 

 and banks. 



3. angnlare. Frond drooping, lanceolate, 

 bipinnate. Pinnules stalked, often pinnatifid, 

 slightly Innulate. p. 7. Shade. 



)3. Braunii, Doll., Rheinfl. Frond more 

 attenuate. Pinnules broadly oblong, trun- 

 cate at base. 

 7. hastulatum. Ten. Frond lanceolate. Lobe 

 on upper side of base of pinnules much 

 prolonged. 



«20. LASTR^A. 



A. Teeth of L. spinescent. 



1. cristata. Frond lineari-oblong, pinnate. 

 Pinnae ovato-triangular, often prolonged, pin- 

 natipartite ; the 3 or 4 lower pair nearly equal, 

 and without fruit. Indusium large, nearly en- 

 tire. Stipe scaly at base. p. 8. Bogs. Norf. 

 Nott. Abbeville. Paris. 



2. spinulosa. Frond oblong, bipinnate. 

 Lowermost Pinnaj without fruit, about as long 

 as the succeeding ones. Indusium entire. Stipe 

 with rounded scales, p. 7, 8. Boggy shade. 



3. dilatata. Frond lanceolate, bipinnate. 

 The lowermost Pinnte shorter than the follow- 

 ing, all bearing fruit. Indusium fringed with 

 stalked glands. Stipe with lanceolate, or 

 ovato-laneeolate, acute scales, p. 7, 8. Shade. 



4. Foenisecii. 



Lowermost Pinnae 

 aU bearing fruit, 

 ged on the edge, 

 lanceolate, acutely 

 Shade 



Ireland, n . Eng. 



Frond ovate, bipinnate. 

 larger than the others ; 

 Indusium somewhat rag- 

 Stipe thickly covered with 

 lacerate scales, p. 8, 9. 

 It is probable that 



j3. lohatum, Sm. Frond 

 hardly bipinnate. 



lineari-Ianceolate, 



L. tanacetifoHa, DC, is one of these ; but the 

 description is not sufficient to identify it. 



B. Teeth not spinescent. 



5. rigida. Frond oblongo-lanceolate, bi- 

 pinnate. Lower Pinnae nearly as large as the 



