Monochoria.} CXXXVI. PONTEDERIACE/E. 1645 



1. TSL. cyanea (blue), F. v. M. Fraym. viii. 44 ; Benih. Fl. Austr. vii. 72. 

 Stems or rhizomes creeping in mud or shortly ascending in water, covered with 

 long thin membranous sheathing scales, one or two of the lower ones produced 

 into a leaf or a long petiole, lamina ovate, acuminate, rounded or cordate at tha 

 base, IJ to Sin. long. Scapes from the axils of the upper sheaths with their 

 terminal leaves at first resembling the lower leaves with a similar lamina, but 

 with a swelling in the middle of the petiole which proves to be the sheathing 

 base of the single leaf, from whence issues a shortly pedunculate loose spike or 

 raceme of 3 to 10 flowers, the base of the peduncle enclosed in a membranous 

 sheath. Flowers sessile or very shortly pedicellate, without bracts. Perianth 

 blue, the segments 5 or 6 lines long or at length rather more, shortly united at 

 the base. Filaments dilated, all nearly equal, without any tooth, one anther 

 often a little longer or smaller than the others but sometimes scarcely different, 

 all opening at first in terminal pores which are afterwards slit down to the base. 

 Seeds ovoid, with 10 to 12 prominent ribs. — Limnostachys cyanea, F. v. M. 

 Fragm. i. 24. 



Hab.: Still waters in southern localities. 



Order CXXXVII. PHILYDRACE.!). 



Flowers hermaphrodite, irregular. Perianth inferior, persistent, divided to 

 •the base into 2 broad petal-like segments, anterior and posterior. One perfect 

 stamen, attached to the base of the anterior segment or almost hypogynous ; 

 filament flattened ; anther variously shaped, attached at the base or adnate, with 

 2 parallel calls, straight or twisted, opening in longitudinal slits ; staminodia 2, 

 hypogynous, alternating with the perianth-segments, flat and somewhat petal-like 

 but small, free or more or less connate at the base with the anther-bearing 

 filament. Ovary superior, 3-celled or with 3 parietal placentre, projecting far 

 into the cavity ; style terminal, simple, with a small or broad terminal stigma ; 

 ovules numerous in each cell or placenta, anatropous. Fruit a capsule, opening 

 loculicidally in 3 valves. Seeds numerous, small ; testa membranous. Embryo 

 small, at the base of a fleshy albumen. — Erect herbs. Leaves linear or flag-like. 

 Flowers sessile and solitary within more- or less sheathing bracts along the 

 rhachis of a simple spike, or along the simple branches of a terminal panicle. 

 The Order is limited to three generas, two represented in Queensland. 



Anther terminal, very much twisted. Ovary imperfectly 3-oelled. Leaves 



flag-like. Spike long, simple 1. Philtdeum. 



Anther erect, on a very short filament. Ovary perfectly 3-celled. Leaves 



flag-like. Spikes in a terminal branched panicle 2. Helmholtzia. 



1. PHILYDRUM, Banks. 

 (A lover of water — plant found in swamps.) 



Perianth-segments many-nerved, the margins slightly involute in the bud. 

 Stamen attached to the base of the anterior segment and not exceeding it ; 

 filament flattened, tapering upwards ; anther terminal, transverse, the cells 

 excessively twisted ; staminodia hypogynous, but often slightly connate at the 

 base with the anther-bearing filament. Ovary 1-eelled, with 3 parietal placentae 

 projecting far into the cavity but not meeting in the centre, each with 2 divaricate 

 broad lobes covered on the inner or under surface with very numerous ovules ; 

 style columnar, with a terminal broad 3-angled stigma. Capsule oblong, 

 opening loculicidally in 3 valves. Seeds very numerous and small, narrow- 

 oblong, brown with black tips, minutely tuberculate, with a short pale funicle. — 

 Tall perennial, with flag-like leaves. Flowers sessile within sheathing bracts 

 along the rhachis of a long terminal spike. 

 The genus is limited to the single species. 



