1968 CLVI. FILICES. [Asplenium^ 



Fronda thinner, 1 to lift, long, } to IJin. broad. Veins mostly 1 ,.,..,-, 



line apart, not connected at the end 2. A. suuphcipong. 



Fronds linear-lanceolate, broken into segments only at the base. 



Veins very oblique, parallel 3- ^- <ittenuatum. 



Fronds simply pinnate. 



Veins more or less tripartite or flabellate at the base of the pinnule, 

 one branch usually elongated and penninerved. 

 Fronds weak, diffuse. Pinnules obliquely obovate or fan-shaped, 



3 to 6 lines broad ■ • i- A. flahelhfohum. 



Fronls diffuse, scaly-hirsute. Pinnules ovate tan-shaped or 



broadly lanceolate, 6 to 9 lines long 5. A.paUaceum. 



Fronds 6 to 13in. long; pinnte with the upper base truncate 

 parallel with the rhachis, inferior base cut off in a curved line 



leaving the midrib at the margin 6.-4. resectum. 



var. austrahensi. 



Fronds attaining 1 to 3ft. Pinnules lanceolate, acuminate, 



IJ to Sin. long 1. A.faloatum. 



Fronds very weak 7 to Sin. long ; pinnae membranous, few to 

 12, 3 to 9 lines long, the lower half cut away nearly to the 



midrib 8. ^. Wildii. 



Veins numerous and parallel from the midrib. Pinnules oblong 



or lanceolate, coriaceous %. A. obtusatum. 



Fronds hipinnate. Segments ouneate, striate. 



Fronds 3 to Sin. long. Sori long and narrow IQ. A. Rookenanum, var. 



Fronds 6 to ISin. long. Primary pinnae lanceolate, IJ to 2in. 



long, with distinct or confluent toothed segments 11. A. furcatum. 



Fronds bipinnate, 3 to 6in. long, the inferior pinnules with a 



large cuneate auricle at the superior base 12. A. afine. 



Fronds 2 to 3ft. long, thrice or four times pinnate, with numerous 



primary and secondary pinnee. Sori small 13. ^1. laserpitii/olium. 



Sect. II. Darea. — Sori oblong or linear on a vein parallel to the margin of the teeth or lobe» 

 and opening towards the margin. 



Sori large with prominent indusia, one to each tooth or lobe of the 

 pinnules. 

 Fronds 1 to 2ft. long, mostly bipinnate ; pinnules lanceolate, ^ to 



lin. long li. A. bulbiferum. 



Fronds mostly pinnate ; pinnules very narrow, 3 to 6in. long . . 15. A. flaccidum. 

 Sect. III. Athyrium.— Sori small, often curved, mostly at the fork of the veinleti proceed- 

 ing from the midrib. 

 Fronds large, membranous, twice or thrice pinnate 16. A. umbrosnm.' 



Sect. IV. Diplazium. — Sori linear along veins pinnately diverging from a central vein to- 

 each lobe of the pinnule. Indusium narrow, opening, in the same frond, on the one or the other or 

 both sides of the nerve. 



Fronds pinnate with pinnatifid pinnae. 

 Ehizome an erect trunk about 1ft. hi^h, 2in. diameter. Pinnae 



linear-lanceolate, petiolulate, 2 to 4in. long . . IT. A. Prenticei. 



Rhizome creeping. Pinnae deeply pinnatifid the lower lobes often 



divided to the midrib .... 18. A.japonicum. 



Bhizome short thick Pinnae pinnatifid with short broal lobes . . 1^. A. S7jlvaticum. 

 Fronds large, bipinnate. Trunk erect or shortly arborescent. 

 Lobes of the secondary plnnEB mostly broad and short. Sori and 



indusia narrow-linear 20. 4. maximum. 



Lobes of the secondary pinnae mostly triangular or lanceolate. 



Sori and indusia short and oblong 21. A. polypcdioides. 



Sect. V. Anisog'onum. — Sori and indusia of Diplazium but the lateral veinlets of each 

 set frequently anastomosing with those of the adjoining set. 



Fronds large, pinnate, the pinnae 6 to 12in. long, 1 to IJin. broad . 22. A. decussattim. 



1. A. nidus (a nest), Linn.; Hook. Spec. Filic. iii. 77, Syn. Filic. 190; 

 lienth. Ft. Amtr. vii. 744. Bird's-nest Fern. Ehizome short and thick. Fronds- 

 ususlly simple, entire, lanceolate, sessile or nearly so in large rep[ular tufts- 

 hollowed in the centre, the 1 irger ones 2 to 6ft. long and 3 to Sin. broad. Veins 

 numerous, nearly transverse, parallel, simple or forked, connected at the end in 

 an intramarginal line. - Sori along the upper or inner side of nearly all the veins,. 



