KKKN FAMILY. 



midrib; divisions very numerous, nearly 1' lone:, somewhat scythe-shaped, 

 rather acute, serrate with incurved teeth ; fruit-dots vcvv near tip- ini'l 



A. cristatuin. Wet places in woods, common : frond > narrowU oi.'onir, 

 1 2 high, 3'- 5' wide, rutlitT rigid, erect; p ir.ue triangular-ovate, bro , 

 at base, pinnatilid almost to the inidril), divisions not nriuv. oblong. ohtu.-e, 

 finely serrate, the largest ones sometimes toothed or pinnaiiiid-lobed ; fruit-dot- 

 half-way between midvein and mar-in. Var. ( 'I.IN m\i VMM. in swampy 

 woods, N., is very mucli larger every wav, with fruit-dots nearer the midvein, 

 and is often mistaken for A. (loldiannm. Var. KI.OIM i>\s i M, in wet wood- 

 S., has the lower pinna; triangular-lanceolate and sterile, but the upper ones 

 fertile, narrower and longer, with very short obtuse rather distant divisions, 

 which are deeurrent on the winged secondary rhaehis. 



t -t Fronds imperferth/ evergreen, twice or thrice pinnate : the d/rixions cut- 

 toothed or incised^: fruit-dots not near the margin: iiidasium rather small, 

 withering aw/iy. 



A. Spinul6sum. Shady woods, very common N. : fronds thin, obloii'_ r - 

 ovate; pinnae oblong-lanceolate, the lower ones broader and somewhat triangu- 

 lar ; pinnules very numerous, oblong-ovate, pinnately inei-ed, the oblong lolies 

 with spinulose teeth toward the ends ; indusium smooth or minutely glandular 

 at the margin. Has several forms. Var. DILATA/PCM, in mountainous place-. 

 N., is larger, broader in outline and commonly but twice pinnate ; pinnule- , ,f 

 the lowest pinna? greatly elongated. Var. Boorm, in swampy woods X, is 

 2-3 high, of narrow outline, barely twice pinnate, with oblong-ovate toothed 

 pinnules, or the lower ones pinnatifid : it runs apparently into A. cristatum. 



- -i- -t- Fronds fufly evergreen, thickish, aJtout twice-pinnate : fruit -dots mar the 

 margin: indusium thickish, convi'x, 



A. marginale. Rocky woods, common N. : fronds l-2 long, ovate- 

 oblong, bluish-green, the stalk very chaffy; pinnae lanceolate, :{' - 5' long; 

 pinnules oblong, often curved, entire or obtusely toothed, attached by a hro.id 

 base to the narrowly winged secondary rhaehis ; fruit-dots close to the margin, 

 rather large. 



2. POLYSTICHUM. Indusium orbicular, peltate, a/f<ir/m/ l>y the centre to a 

 short stulk: veins forking, free : wild species of the country. 



A. acrostichoides. Rocky woods, common; fronds 1 - 2 high, grow- 

 ing in crowns, with chaffy rootstoeks au;l stalks, evergreen, shining, lanceolate, 

 simply pinnate; pinnae numerous, oblong-lanceolate from an minimal halt- 

 halberd-shaped base, serrulate with bristle-pointed teeth, rarely inci-e,!, upper 

 ones of the fertile frond smaller and bearing copious soon continent fruit-dot-. 



3. CYRTUMIUM. Indusium as in POLYSTK'IIITM. Fronds once pinnule : 

 vein* pinnate from the midrib, pinnalelu branching, the rrinli''.* reticulated 

 and for mi mi arched meshes with 1-3 free included veinlets rising from the 

 base of the arch : exotic. 



A. falcatum. Cult, from Japan: fronds l-2 hUrh, 5'-9' broad : base 

 of stalk chaffy with large scales; pinnne thick and shining, end one large and 

 rhomboid or halberd-shaped ; side ones few or many, oblong-ovate, long-pointed, 

 nearly entire, lower side of base rounded, upper side an-lcd or slightly auricle 

 fruit-dots in many rows on all or nearly all the pinnaj. 



16. CYSTOPTERIS. ( Greek for Bladder /-V, alluding to the thin, 

 sometimes inflated indusium.) Species few, mostly Northern. 

 C. fragiliS. Shaded or moist rocky places, common X. : fronds very .1 

 cate, 4'-8 : long, with slender stalks, oblong-ovate, twice-pinnate; pinnae 

 a narrowly margined rhaehis; pinnules oblong or ovate, toothed or incised, rery 

 variable; indusium pointed at the upper end. 



C. bulbifera. Wet places, ol'tene-t in ravines, from X 

 fronds 1- 3 high, 3' -5' wide at the base, narrowed above and much e 

 gated, twice pinnate, bearing scattered bulblets beneath ; pinnule- oblon-. ob- 

 tuse, toothed or pinnatifid ; indusium roundish, truncate on the upper ride 



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