1510 CXXV. HYDEOCHAEIDE^. [Dlyxa. 



linear anthers not exceeding the outer perianth-segments. Female spathe 

 usually longer and more slender than the male, the ovary much shorter, but the- 

 perianth-tube projecting above Jin. from the spathe, the segments narrower than 

 in the males. Fruit narrow, entirely enclosed in the spathe, varying from 1 to-. 

 2in., the seeds not very numerous. — ValKmeria octaniha, Roxb. PI. Gorom. ii. 34,. 

 t. 165 ; Bhjxa octandra, Planch. Mss. ; Thw. Enum. PI. Ceyl. 332. 



Hab.: Water-holes Eoekingham Bay and Burdekin Eiver, Dallachy, and many of the- 

 northern waters. 



4. HYDROCHARIS, Linn. 



(A graceful water plant). 



Flowers dioecious. Males 2 or 3 together in a spathe of 2 bracts. Outer 

 segments of the perianth green, inner ones larger and petal-like. Stamens usually 

 9 with anthers, and 3 barren filaments, the filaments united in pairs. Female- 

 flowers solitary and pedicellate within the spathe. Ovary and fruit 6-celled. 

 Styles 6, each with 2 stigmatic branches. — Stems floating, with tufts of radical 

 leaves and peduncles. Leaves bearing a cordate lamina. 



The genus is limited to a single species spread over Europe and the temperate regions ot 

 Asia, the Australian specimens presenting no apparent difference. 



1. H. morsus-ranae (from the English name "Frog-bit"), Linn. Spec^ 

 PL 1466; Benth. Fl. Austr. vi. 256. Stems floating, resembling the runners of 

 creeping plants, with floating tufts of radical leaves peduncles and submerged 

 roots. Leaves on long petioles expanded into a sheath at the base, orbicular,, 

 entire, cordate at the base, but less deeply so in the Australian than in the- 

 European specimens, rather thick, 1 to 2in. diameter. Male spathes ^ to lin.. 

 long, on peduncles of about the same length, the flowers shortly exserted. Inner 

 perianth-segments white, 4 or 5 lines long, outer ones about half as long and 

 green, all very broad.' Stamens united in six pairs, the pairs opposite the outer 

 , segments with both filaments bearing anthers, those opposite the inner segments 

 with the inner filament barren. Anther-cells bordering a broad connective^ 

 Female spathe sessile, the flower on a rather long pedicel enlarged at the top into- 

 an inferior ovary, the perianth nearly the same as in the males. Fruit ovoid, 

 somewhat fleshy, under ^in. long. — L. C. Eich. in Mem. Inst. Fr. 1811, t. 9; 

 Eeichb. Ic. Fl. Germ. t. 62. 



Hab : The still waters about the Brisbane Eiver ; Wide Bay, Bidmll. 



5. OTTELIA, Pers.- 



(Damasonium, Schrei., not of Juss.) 

 Flowers hermaprodite, solitary and sessile within a tubular 2-lobed spathe. 

 Outer perianth-segments green, inner ones larger and petal-like. Stamens 6 or 

 more ; anthers linear. Styles or stigmas 6, 2-lobed. Ovary and fruit more or 

 less completely 6-celled, with numerous ovules and seeds. — Submerged herbs, the 

 radical leaves and peduncles in tufts at the bottom of the water. Leaves mostly 

 or all bearing an oblong ovate or broad-cordate lamina. 



The genus is spread over tropical Asia and Africa with one American species. Of the two 

 Australian species, one is the common Indian one, the other apparently endemic. 



Leaf-lamina broadly cordate. Spathe winged 1. 0. alismoides. 



Leaf-lamina ovate or oblong. Spathe not winged, firm, the outer perianth- 

 segments protruding and persistent on the fruit 2. 0. ovalifoUa. 



1. O. alismoides (Alisma like), Pers. Syn. PI. i. 400; Benth. Fl. Austr. vi. 

 257. Leaves on long petioles dilated and tufted at the bottom of the water, the 

 lamina submerged or floating, orbicular-cordate and about 6in. diameter. 

 Peduncles usually long. Spathe ovoid-oblong, nearly l^in. long, shortly 2-lobed 

 at the top, and bearing 5 or 6 longitudinal herbaceous wings, 2 or 3 of them 1 ta 



