3G8 FERN FAMILY. 



* Fronds tivice jiinnalifid.-the sessile pinnae mostli/ Jorming an irregular and 

 many-uru/led wing along the rhachis. 



P. polypodioides, formerly Polyp6dium PHEcdrTERis. Common N. : 

 fronds 4' -9' long, longer than broad, triangular-ovate, sligbtiy hairy beneath; 

 pinnsB lanceolate, the lower pair turned obliquely forwards ; secondary divisions 

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



P. hexaKOndptera. Common K. & S. : larger than the last, which it 

 much resembles, but the frond is broader than long ; lowest pinnae n)uch the 

 largest and with elongated and pinnatifid divisions ; &uit-dots not exclusively 

 near the margin. i 



» * Fronds with three primary divisions, which are stalked, rhachis wingless. 



P. Dry6pteris. Common N. : fronds broadly triangular, 4' -6' wide, 

 smooth ; the three primary divisions triangulai', once or twice pinnate with ob- 

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



15. ASPIDIUM, SHIELD-FERN. (Greek for a litUe shield, referring to 

 the indusium. ) — A very large genus, inhabiting all parts of the world. 



§ 1. Nephr6dium or Dry6ptebis. Indusium round-kidney-shaped or nearly 

 circular with a narrow clejlfrom the lower side almost to the centre. 

 » Fronds thickish, simply pinnate, the few pinnae entire or nearly so. 



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

 high, with 2-4 pairs of side pinnae, each 4' - 6' 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-liouse plants), pinnate .• 

 pinnae simply pinnatifid with mostly entire obtuse lobes : indusium small. 



t- Sootstock creeping, slender, nearly naked and bearing scattered fronds : veins 

 free, simple or once forked : wild species, common in bogs and low grounds. 



A. Thel^pteris. Fronds lanceolate, 10'- 18' long, on slender stalks, 

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

 turned down, the lowest pair scarcely shdrter ; divisions oblong, fruiting ones 

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

 fluent when ripe ; indusium smooth. 



A. n'oveborac^nse. Much like the last, but hairy beneath along the 

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

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

 veins rarely forked ; fruit-dots distinct ; indusium slightly glandular. 



■*- -»- Rootstock oblique or erect, stouter, bearing tite fronds in a crown ; veins simple, 

 free, or the lower ones of contiguous lobes united: indusium hairy. 



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

 sparsely pubescent, ovate-oblong; pinnae 3' -6' long, i' wide, numerous, lance- 

 olate from a broad base, lowest pairs a little smaller ; divisions oblong, slightly 

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



A. mdlle. Cult, from tropical <ountries : very much like the last, but ev- 

 erywhere downy or soft-hairy ; pinnae less deeply lobed ; lobes obtuse ; lower 

 veinlets (1 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 

 stout and chaffy rootstock, and often remaining green through the winter . 

 veins 2 - i-forked or branching. Wild species of the country. 



*- Fronds imperfealy evergreen, once pinnate with deeply pinnatifid pinnae, or 

 nearly twice pinnate: fruit-dots not. close to the margin: indusium rather 

 large, fiat, smooth, persistent. 



A. Goldiiuium. Kich moist woods N. : fronds broadly ovate, 2° - 4" high, 

 9' -12' wide; pinnae oblong-lanceolate, broadest about the middle, parted to the 



