3G8 FERN FAMILY. 



* Fronds twice pinnaiijid : the sessile pinnce mostly forming an ii regular and 



ma 1 1 1/ -any led wing along the rliac/iis. 



P. polypodioldes, former.y POLYPODIUM PHEGOPTERIS. Common N. : 

 frond;, 4'-<y louy, longer than broad, triangular-ovate, slightly hairy beneath; 

 pinna; lanceolate, the lower pair turned obliquely forward .; ; secondary divisions 

 crowded, oblong, obtuse, entire; fruit-dots all near the margin. 



P. hexagonoptera. Common X. & S. : larger than the last, which it 

 much resembles, b..t the frond is broader than long; lowest pinna: much the 

 largest and with e.ongated and pinnatilid divisions ; fruit-dots not exclusively 

 near the margin. 



* * Fronds with three primary divisions, which are staled, rhacliis wingless. 



P. Dry6pteris. Common X. : fronds broadly triangular, 4'-G' wide, 

 smooth , the three primary divisions triangular, once or twice pinnate with ob- 

 long obtuse entire or toothed lobes ; fruit-dots near the margin. 



15. ASPIDIUM, SHIELD-FERX. (Greek for a little shield, referring to 

 the indusium.) A very large genus, inhabiting all parts of the wor.d. 



1. NEPHu6niUM or DRYOPTERIS. Indusium round-kidney -shaped or nearly 



circular witli a narrow clef I from the loiwr side a/most to the ceiitre. 

 * Fronds thicki.Ji, simply pinnate, thejtw pinixr entire or nearly so. 

 A. Siebbldii. Cult, from Japan : fronds coriaceous, smooth, about 1 

 high, with 2-4 pairs of side pinnae, each 4'-G' long and nearly 1' wide, and a 

 terminal one rather larger than the others ; veins with 4-6 free parallel branch- 

 es ; fruit-dots large, scattered in several rows. 



* # Fronds thin, decaying in early autumn (or tender hot-house plants), pinnate.' 



pinnce simply pinnatijid with mostly entire obtuse lobes : indusium small. 



+- Rootstock creeping, slender, nearly naked and bearing scattered frond* : reins 

 free, simple or once forked : wdd species, common in l>oys and low grounds. 



A. Thetypteris. Fronds lanceolate, 10' -18' long, on slender stalks, 



nearly smooth; pinnae lanceolate, 2' -4' long, about ' wide, spreading or 



turned down, the lowest pair scarcely shorter ; divisions oblong, fruit. ng ones 



inning acute from the revolute margins ; veins mostly forked ; fruit dots con- 



Hucnt when ripe ; indusium smooth. 



A. Noveboracense. Much like the last, but hairy beneath along the 

 rhnchis and veins ; fronds tapering both ways from the middle ; lower pinna 

 gradually smaller nnd distant ; lobes flat, the basal ones often larger and incised ; 

 ve.ns rarely forked ; fruit-dots distinct; indusium slightly glandular. 



*- *- Rootstock ob/i<fne or erect, stouter, l>earing the fronds in a croicn : veins xtmple, 

 free, or the lower ones nf contiguous lobes united: indusium I, airy. 



A. patens. Low shady grounds, Florida and W. : fronds l-2 high, 

 sparsely pubescent, ovate-ob!ong ; pinnae 3'-G' long, A' wide, numerous, lance- 

 olate Irom a !>road base, lowest pairs a litilc smaller ; divisions oblong, slightly 

 falcate, obtuse or acutish ; veins entirely free; indusium slightly hairy. 



A. mdlle. Cult, from tropical (ountr.es: very much like the last, but ev- 

 erywhere downy or solt-liairy; pinna 1 , less deeply lo'ied ; lobes o'ltiiM-; lower 

 verniers (I or '2 pairs) uniting with the corresponding ones of contiguous lobes 

 and sending out a ray-like veinlet to the sinus ; indusium very hairy. 



* # * Fronds smooth, from once to thrice pinnate, growing in a crown from a 

 xtont and r/i'tf/'i/ root slock, and oj)<i\ nniaining qwn through the Winter: 

 rt-ins 2 - 4-/ork<d or branching. IT/A/ spn-it-x of the country. 



+- Frondu imperfectly evergreen, once, pinnate n'/th de.e/>l// pinna/ i /id pinnce. or 

 ninr/i/ liria- pinnotf: ffnit-dott not close to the nmrgiu: indusium rather 

 Ifii'/c, fliif, smooth, pernittentt 



A. Goldianum. Rich moist woods N. : fronds broadly ovate,, 2 - 4 high, 

 9' -1 2' wide,; pinnaj oblong-lanoeolate, broadest about the middle, parted to the 



