200 FLORA OF SOUTH AUSTRALIA. 
Marsilea. 
Barren fronds glabrous or hairy ; leaf-like segments cuneate- 
ovate... 3k xe On if. ia, Ae ... quadrifolia 
Pilularia. 
Barren fronds 1 to 3 in., bright-green ; fruit-masses like little 
pills, 14 to 2 lines diameter, » slightly Seid as by 
4 valves ae ae ... Qlobulifera 
ORDER FILICES. 
1. Spore-cases globular, 2-valved, without any 
ring, sessile in 2 rows. Fertile fronds 
spike-like, simple or branched, often con- 
nate at the base with the barren frond. 
Barren frond solitary, undivided ; fertile frond, a simple 
spike... 4 shy th ... Ophioglossum 
Barren frond bltiaiy, scene evbie frond, a pan- 
iculate spike... ny ie) oe Bo .. Botryehium 
11. Spore-cases globular, without any perfect 
ring, 2-valved ; sessile in 2 rows covering 
the inner surface of the pinnules. Erect, 
simple, or dichotomous fronds, without 
expanded laminae... aD sd .. Sehizaea 
111. Spore-cases globular, with a transverse ring, 
opening vertically into 2 valves. 
Sori of 2, 3, or few spore-cases to each segment of the 
pinnules. Frond dichotomous, segments of the 
pinnules in two rows ... ; Gleichenia 
Sori of numerous spore-cases on ‘iy reste side = MBS 
contracted frond-segments. Fronds bipinnate ... Osmunda 
Iv. Spore-cases with a longitudinal ring, rup- 
tured irregularly, stalked; sori on the 
underside or rarely at the margin of the 
frond. 
a. Sori covered at least when young with an 
indusium. 
Sori globular, close to the margin ; indusium adnate on 
the upper side, opening in 2 valves ... p ... Dieksonia 
Sori linear, marginal ; indusium membranous, opening 
from the mar gin inwards... ; ur ... Lindsaea 
Sori marginal; indusium continuous iit the margin 
and opening from the outer edge outwards. 
Sori short ; frond compound, veins of the pinnules 
forked radiating from the stalklet ms .. Adiantum 
