24 I. — FiLiCES. [Gleichenia 



Section II. — Sorus naked. 



Family VII. — Polypodies. Sori on tlie 

 hack of the frond rownded or rarely 

 oblong, never more than twice as long 

 as broad (PI. III. figs. 6-7.) ... 23. Polypodium. 



Family VIII. — Grammitidese. Sori on tlie hack of tlie frond 

 usually linear, always more tha/n twice as long as broad. (PI. III. 

 figs. 8-9.) 



Sori continuous within the margin of the 

 frond, which is often partially re- 

 curved over them as a pseudo-invol- 

 ucre 24. Nothochlsena. 



Sori on the veins, spreading over the 

 under surface of the frond in simple 



or branched lines 25. Gymnogramme. 



Tribe V.^ — Osmundese. 



Capsules large, vertically 2-valved, fur- 

 nished with a short transverse ring, 

 not forming regular sori, but clus- 

 tered irregularly on the back of the 

 frond (PI. III. fig. 10.) 26. Todea. 



Tribe VI. — Schizseacese. Capsules 2-valved, opening down the 

 side, crowned by a complete ring on the apex like a cap, arranged in 

 spikelets. (PI. III. fig. 11, and PI. IV. fig. 1.) 



Capsules sessile in 2 rows on one side of 



close spikes, which are pinnately- <* 



arranged at the apex of the fronds ... 27. Schizsea. 



Capsules solitary in the axUs of scales 

 which form spikes, either on separate 

 pinnse or on the margins of the leafy 

 ones. Stems widely-climbing ... 28. Lygodium. 



Tribe VII. — Marattiacese. Capsules 612, united together into a 

 boat-shaped sorus or synangium, which is placed near the end of a 

 vein on the back of the frond. (PI. IV. fig. 2.) 



Fronds very large, 2-pinnate 29. Marattia. 



Genus I.— GLEICHENIA,* Smith. (PL I. fig. 1.) 



Rhizome creeping, wiry and rigid. Fronds usually dicLotomously 

 branched, with a terminal bud at each fork ; branches forked or 

 pinnate, sometimes whorled. Pinnae deeply pinnatifid; segments 

 small, concave and suborbicular, or pectinate with elongated lobes. 

 Sori of 2-4 or 10-12, sessile capsules opening vertically, and girt by 

 a broad, transverse, complete ring. 



* In honour of Baron von Gleichen, a German botanist. 



