KEY TO THE FAMILIES AND GENERA 



135 



212. EQUISETACE^;. 

 One genus only Equiaetum. 



ccc. Indusia inferior, attached under 

 the sorus and opening laterally 

 or by splitting radially into lobes. 8. WOODAIA TRIBE. 



213. OPHIOGLOSSACE^. 



A. Sporangia coherent, in 2 ranks, forming 



spikes: veins anastomosing f . 1. Ophioglos- 



AA. Sporangia free in compound spikes or pani- [sum. 



cles: veins free: Ivs. mostly compound 2. Botrychium. 



214. MARATTIACE^E. 



A. Sori in double lines along the veins, not 



united 1. Angiopteris. 



AA. Sori united in synangia. 



B. Synangia oval, opening by a fissure 2. MaraUia. 



BB. Synangia elongate, each compartment open- 

 ing by a terminal pore : 3. Dantea. 



215. HYMENOPHYLLACE.fi. 



A. Involucre 2-valved 1. Hymeno- 



[phyllum, 



AA. Involucre tubular or funnel-shaped 2. Trichom- 



[anes. 



216. OSMUNDACE.E. 



A. Sporangia borne in panicles formed either 



from certain pinna- or from whole Ivs 1. Osmunda. 



AA. Sporangia borne on the under surface of foli- 

 age Ivs. 



B. Ferns coarse with broad segms 2. Todea. 



BB. Ferns finely cut, membranous 3. Leptopteris. 



217. 



A. Sporangia borne on under side of normal or 



altered lys. 

 B. Lvs. twining; Ifts. palmate or pinnate: 



sporangia borne singly under scale 1. Lygodium. 



BB. Lvs. not twining. 



c. Sporangia in sori on the under surface 2. Mohria. 



cc. Sporangia in 2 ranks forming spikes 3. Schiznea. 



AA. Sporangia borne in erect panicles formed on 



the elongate lowermost pinnae 4. Anemia. 



218. POLYPODIACE-ffi. 

 /. Summary of Tribes. 



A. Indusium wanting or rudimentary 



(rarely developed in Monogramma). 



B. Sporangium scattered in a stratum 



over the under surface of the Ivs.: 



coarse ferns 



BB. Sporangium collected in round or 



linear sori. 

 c. Lvs. not jointed to the rootstock: 



rrangia in long lines following 

 veins 



cc. Lvs. not jointed to the rootstock: 

 sori round. (See Phegopteris in 

 Dryopteris Tribe.) 

 Ccc. Lvs. jointed to the rootstock: sori 



mostly roundish 



AA. Indusium present (exceptionally want- 

 ing in Phegopteris, Meniscium, 

 Notholsena and Ceropteris). 

 B. Sori oblong or linear, at least twice 



as long as broad. 



c. The sori marginal, covered with an 

 indusium formed of the reflexed 

 edge of the If. (naked in Notho- 

 Isepa, or naked and distributed 

 along the veins in Ceropteris) . . . . 

 cc. The son dorsal, covered with a 



flap-like indusium 



BB. Sori roundish or at least less than 



twice as long as broad. 

 c. Indusia superior, attached by a 

 central stalk or by a sinus (sori 

 naked in Phegopteris and Menis- 

 cium), normally dorsal: Ivs. not 



jointed to the rootstock 



CC. Indusia extrorse or cup-shaped, 

 normally marginal: Ivs. jointed 

 to the rootstock in most genera . . 



1. ACROSTICHCM 



[TRIBE. 



2. VITTARIA TRIBE. 



3. POLYPODIUM 



(TRIBE. 



4. PTERIS TRIBE. 



5. AspLENitJM TRIBE. 



6. DRYOPTERIS 



[TRIBE. 



7. DAVALLIA TRIBE. 



//. Key to the Tribes. 



1. Acrostichum Tribe. 



A. Sporangia localized on definite areas of the Iva. : 

 lys. dimorphous, the sterile basal ones shield- 

 like 1. Platycerium, 



AA. Sporangia covering entire Ivs. or entire pinna;. 



B. Lvs. simple 2. Elapho- 



[glosaum. 



BB. Lvs. pinnate 3. Acrostichum* 



BBS. Lvs. (sterile), dichotomously forked 4. Rhipidop- 



[tsris. 



2. Vittaria Tribe. 



A. Son forming 1 or 2 continuous lines parallel 

 to the midrib. 



B. Sorus 1 or 2 lines 5. Mono- 



[gramma. 



BB. Sprus always 2 lines 6. Vittaria. 



AA. Sori on lateral veins forming more or less 



interrupted lines 7. Antropk- 



[yum. 



3. Polypodium Tribe. 



A. Lvs. distinctly dimorphous, compound, the 



sterile basal ones oak-like: plants large 8. Drynana. 



AA. Lvs. dimorphous, simple: plants very small.. . . 9. Drymo- 

 AAA. Lvs. uniform. [glosntm. 



B. Foliage covered underneath with stellate 



hairs 10. Cyclophorua. 



BB. Foliage smooth or scaly, not stellate hairy. 



c. Veins free 11. Polypodium, 



cc. Veins anastomosing. 



D. Corresponding veinlets from principal 

 veins uniting and bearing a sorus at 



the end 12. Goniophle- 



DD. Areole bearing 2 or more free veinlets [bium. 



extending outward, which bear a free 



sorus 13. Phlebodium. 



ODD. Areoles containing free veinlets irregu- 

 larly directed 14. Phymatodea. 



4. Pteris Tribe. 



A. Son dorsal, extending along all the veins, 



naked. 

 B. Veins copiously anastomosing. 



c. Lvs. large, pinnate 15. Conio- 



[fframma. 



cc. Lvs. smaller, palmate 16. Hemionitis. 



BB. Veins free or only casually uniting. 



c. Lvs. naked 17. Anogramma. 



cc. Lvs. hairy f 18. Ceropteria. 



AA. Sori marginal, nominally covered with edge 



of If. 

 B. The sori at the ends of veins unconnected at 



their apices, 

 c. Lvs. dimorphous. 



D. Sori at the ends of veins only 19. Crypto- 



[gramma. 



DO. Son scattered the length of the veins ... 20. Onychium. 

 cc. Lvs. uniform, smooth, on dark-colored 

 stalks. 



D. Veins free: Ivs. pinnate 21. PeUsea. 



DD. Veins usually anastomosing: Iva. 



palmate 22. Doryopttri*. 



ccc. Lvs. uniform, hairy, scaly or powdery. 



D. Margins scarcely recurved 23. NothoUena. 



DD. Margins recurved to form a distinct 



indusium. 



E. Indusia more or less continuous 

 around the segm. 



r. The Ivs. pinnately divided 24. Cheitanthea. 



FF. The Ivs. palmately divided 25. Adicmtopaia. 



BE. Indusia in the form of more or less 



distant marginal lobes 26. Hypolepia. 



BB. The sori inserted beneath the marginal 



indusium : stalks black or blackish 27. Adiantum. 



BBB. The sori rising in a continuous line-like 

 receptacle which joins the ends of the 

 veins. 



c. With an inner membranous indusium 28. Pteridium. 



cc. With no inner indusium present. 



D. Lvs. small, radiate-dichotomous 29. Actinopteris. 



DD. Lvs. small, palmate: stalk black 30. Coaaebeera. 



ODD. Lvs. larger, pinnate 31. Pieria. 



5. Asplenium Tribe. 



A. Sori parallel to the midrib. 



B. Sterile Ivs. with free veins: sori continuous . . 32. ftltchnum. 



