PTERIDIUM 



sporangia borne on a marginal line-lilte receptacle as in 

 Pteris (Fig. 2011) and covered with a marginal indu- 

 sium, Init with an additional membranous indusium 

 within the receptacle. Commonly known as Pteris. 



aquilinum, Kuhn. Lvs. scat- 

 tered fniiii nil underground rhi- 

 zoiiir, J-'.i ft. hi^'li. temately com- 

 pound. Kirld and waste places in 

 some 'd' its t'>nii> throughout the 

 world. L, '\i, Undekwood. 



PTERIS (Greet 



1463 



. refers to supplementary list. 



A. Wilis fl-rv lln-nil'lhnilt. 



B. /.<•,.. ,w„,,,/7 in„,i.,t.-. Iho Inir.r 



pniii.t iini ,iir,,lr,l 1 . longifolia 



BB. /.-■.. sui,lil,l imuint,:, hill Ihr 



l<',r, r jniiini liirke'l -J. Cretica 



:i. serrulata 



4. ensiformis 



BBB. Lvx. with lowest pinnie pinnate. .'>. inaequalis 



C. semipinnata 

 BBBB. Lvs. with lowest pinnm bipin- 

 natifid. 



c. Lowest pinnce enlarged 7. quadriaurita 



«. heterophylla 

 '.I. tremula 

 00. Lowest pinnw not enlarged ..10. scaberula 

 AA. Veins free, except for a single tow 



arch next the midvein 11. biaurita 



12. Wallichiana 

 AAA. Vein,'* unitinq, forming copious 



meshes 13. leptophylla 



1. longifdiia, Linn. Lvs. 1-2 ft. long, 4-9 in. wide, 

 lanceolate, often narrowed below; pinnae 20-30 on each 

 side, linear, entire. Tropical regions all around the 

 worlil, e.Ktendlng to southern Florida. Var. H&riesii, 

 Hnrl. Fronds shorter and pinnules straighter, the plant 

 kct-pinK closer to the pot; a good horticultural form. 



2. Cretica, Linn. Lvs. 6-12 in. long, on slender, straw- 

 colored stalks, consisting of a terminal pinna and 2-6 

 opposite sessile pairs, the upper often deciirrent. the 

 lower ii.iirs cleft nearly to the base iTit" L' ^r :: ],ii,iinlr-. 

 (,tuite uotierally distributed introjdenl i .: < ■.!!'] 



ill- I -iitral Florida. Manyvarieii. of 



whi.-li \ ;ir. albo-Uneita, Hort. (Fig. l'"I ' , . i. ; ilie 

 liie-i, with broader pinnip and a broa-l. ■ m i al. ., Ii:tisli 

 band. Var. m&jor and var. nbbiUs are lartjir liorlieul- 

 tnral forms, and var. magnifica and var. Miyii (P. 

 3Iai/ii) are still more developed. 



3. aerrulAta, Linn. f. Lvs. :t-12 in. long, on slender 

 brownish stalks, consisting of a terminal pinna and 5-6 

 pairs of lateral ones, the upper ones decurrent and the 

 lower firked into 2 or 3 br.anches or with second branch 

 above the basal one: pinnse narrow, the indusium not ex- 



serrulate. China 

 ■ted forms appear 

 HN as angnstita, 

 stata variegita, 

 . . Holt. I, volilta. 



but these 



any scientific sense. 



4. ensifdrmis, Burm, Lvs. of 2 sorts, the sterile with 

 elliptic or elliptic-lanceolate segments, the lower pinnse 

 5-7-parted, the upper [.'radually simpler; sporophylls 



u'.;er and much narrower 

 often confused with the 

 more or less common in 



"' , Hort. ) is a garden va- 



■ith white. 



imilar but 

 divisions. Lull. 

 preceding s]'m 

 cult. Var. Victo 

 riety with leave 



5. insequiiUs, Baker. Lvs. ovate -deltoid, 18-24 in. 

 long, 10-15 in. wide, with 4-5 pairs of pinnate or pinnati- 

 fid pinnsB followed by 2-3 pairs of broadly linear simple 

 ones and ending in a long, terminal, irregularly pin- 

 natifld portion; divisions of the lower sides of the pin- 

 nse uniformly much longer and larger than the upper 

 ones. China and Japan. 



CXM) 



6. semipinnata, Linn. Lvs. 12-18 in. long, the upper 

 portion simply pinnate with decurrent pinnse, the 4 or 

 more lowest pinnatifid on the lower side, the upper side 

 of the secondary rachises bordered by a narrow lamina. 

 India, China, Japan and the East Indies. -Var. Batisei, 

 (P. Bai'isei, Hort.) is a garden form. 



7. quadriaurita, Retz. Lvs. up to 2-3 ft. long, on 

 strong, pale stalks, with a terminal central pinna cut 

 down to the rachis into numerous linear-oblong lobes, 

 and below this several similar pinnse on each side, the 

 lowest of which are usually again compound with simi- 

 lar but smaller ones branching from the lower side at 

 base. All tropical regions.— Var. argyrsea {P. argyrtea, 

 Moore) is a form with a white band down the centers 

 of the pinnaj. Var. tricolor (P. Iricnlnr, Linden) is simi- 

 lar but has a tinge of red in addition. 



8. heterophyUa, Linn. Lvs. 6-8 in. long, on pale stalks, 

 of 2 sorts ; sterile lvs. elliptic, deeply incised ; sporophylls 

 narrowly linear-elliptic, with broad indusia and sterile 

 apices endinir in 2-3 teeth: both sorts bipinnate in the 

 lower portion-. West Indies to Brazil. Sometimes 

 referre.l t,, i ,li-iin,t ^.-enn-. .\nopteris. Var. intem&ta 

 i.P. int< ,„.,'./. .Mo.in 1 i- a L'arden variety with smaller 

 sporopli>lls rind broader sei^inents. 



