12 FLORA OF SOUTH AUSTRALIA. 
Clasping leaf-stalks with free margins; stems usually 
hollow, jointed, round ; flowers in more or less scari- 
ous spikes called spikelets; 2 or 3 scale-like bracts 
called glumes subtending the spikelet; true floral- 
segments usually absent, rarely of 3 pellucid scales 
called /odicules ; each flower usually enclosed in a 2- 
nerved scale called a palea (regarded as 2 connate 
bracteoles) and an outer scale or flowering glume ; 
styles 2, usually feathery ; stamens 1 to 4, usually 3 Gramineae 
CLASS III.—VASCULAR ACOTYLEDONS. 
Spore-cases in spikes, supported by bracts, in the axils 
of leaves or at the summit of the branches ... Lyeopodiaceae 
No true leaves ; foliaceous organs or fronds circinate in 
vernation. 
Barren fronds linear or with leaf-like laminae ; fer- 
tile fronds, often emanating at or near the roots, 
forming a closed involucre including the spore- 
cases, containing spores of two kinds _... ... Rhizospermae 
Fertile fronds bearing the spore-cases on their 
under side or margins ; spore-cases stalked or 
sessile, with or without an encircling elastic ring, 
opening by regular slits, or by rupture ... =~» alices 
