raUmuria.] CXXV. HYDROCHAEIDE^. 1509 



1. V. spiralis (spiral), Linn. Sp. PL 1441 ; Betith. FL. Austr. vi. 259. 

 Leaves with often a long portion floating or entirely submerged, very long and 

 narrow when the water is deep, short in shallow water, obtuse or acute and more 

 ■or less serrulate at the end with minute teeth, or sometimes perhaps quite entire. 

 Male spathes about 3 lines long, on a peduncle usually short, but breaks 

 •off and enables the flower to float to the surface and fecundate the female. 

 Flowers minute, apparently forming an ovoid or globular head not quite so long 

 -as the spathe, but the pedicels' really 3 or 4 times as long as the minute perianth. 

 Female spathe usually about -^^in. long, yery narrow, on a spirally coiled filiform 

 peduncle, which unfolds so as to carry the flower to the surface till after fecunda- 

 tion, when it contracts and brings the ovary down to the bottom to mature. 

 Perianth very small but larger than in the males. Fruiting spathe only slightly 

 enlarged.— Eich. Mem. Inst. Fr. 1811, t. 3 ; Eeichb. Ic. Fl. Germ. t. 60 ; Hook, 

 f. Fl. Tasm. ii. 37 ; 'V. spiralis and V. nana, R. Br. Prod. 345. 



Hab.: Burnett Eiver, ii". v. Mueller; between Cleveland and Bockingham Bays, W. Hill; 

 Fitzroy river, O'Shanesy, several feet long ; common in the rivers north and south. 



2. V. gracilis (slender), Bail. 3rd. Suppl. Si/n. Ql. Fl. 70. Stems slender, 

 creeping in the mud. Leaves about 7 or 8 to a plant, very narrow like fine grass, 

 :3 to 5in. long and about |-line broad, the sheathing base short, tapering to 

 filiform points, all submerged, no portion floating on the surface of the water. 

 Male flowers minute ; female flowers on very fine filiform spirally twisted stalks ; 

 perianth of 3 ovate entire segments ; stigmas 3. 



Hab.: Still waters, or at the edge ot the running waters of the Mulgrave River. 

 The above is from note made on the spot, and having but a common lens I could not fully 

 •describe the flowers. 



3. v. caulescens (stemmed). Bail, ct F. r. ]\[. 2nd Siippl. Siju. Ql. Fl. 56. 

 Stems submerged, leafy, lengthening to 18 inches or ' more, resembling a 

 Potamugeton. Leaves numerous, linear, obtuse, from IJ to 3in. long and about 

 -Jin. broad. The few specimens collected show 4 to 3 spathes in the axils of the 

 lower leaves ; in the upper axils, however, they are solitary, and all sessile. Calyx- 

 itube under the lobes gradually contracted. 



Hab.: Found in the M. Lagoon, about 60 miles west of Normanton, by Dr. Tlios. L' 

 Bancroft. 



3. BLYXA, Thou. 



Flowers usually dioecious. Males several, protruding when open from a 

 tubular 2-toothed spathe. Perianth-segments all linear, the 3 outer ones green, 

 the 3 inner longer and petal-like. Stamens 8 or 9 ; anthers linear. Female 

 flowers solitary in the sheath, the ovary sessile ; perianth-tube above the ovary 

 long and filiform, the segments as in the males or narrower. Style exserted, with 

 3 linear stigmas. Ovary narrow, with parietal placentas. Fruit narrow, 

 ■enclosed in the spathe. Seeds many. — Submerged herbs, the leaves long and 

 grass-like without laminfe, acute and entire, tufted with the peduncles at the 

 bottom of the water. 



Besides the Australian species, which is spread over tropical Asia, there is another from the 

 Mascareue Islands. 



1. B. Itoxburghii (after Dr. Eoxburgh), Bich. in. 2Ieni. Inst. Fr. 1811, 

 '77, t. 6 ; Benth. Fl. Austr. vi. 258. Leaves entirely submerged, long and 

 narrow like those of Vallisneiia spiralis but more acute and not serrulate. Spathes 

 both male and female on long slender peduncles, the males about Ij to 2in. long, 

 ■containing several flowers, but usually only 1 to 3 protrude at the same time, on 

 pedicels several lines longer than the spathe. Outer perianth-segments about 21- 

 iines long, the inner twice as long. Stamens about 8, the filaments short, the 



