2 cxxxi. HYDROCHARiDEiE (wbight). [ffydrUla. 



Female spathe tubular, bidentate. Perianth segments 6, narrower 

 than in the male. Staminodes 0. Ovary produced beyond the spathe 

 into a long filiform beak, 1 -celled ; placentas 3, rarely 2 ; styles 3. 

 Ovules few, anatropons. Fruit narrow, slightly exserted from the 

 ruptured spathe. Seeds oblong ; spermoderm slightly produced at each 

 Qnd. — Aquatic herb, with submerged, branched stem. Leaves verti- 

 cillate. Flowers small, solitary in the axils of the leaves. 



This genus consists of a single variable species widely spread through Tropical Asia, 

 the Mascarene Islands, and Australia. 



1. H. verticillata, Royle, III. Bot. Himal. 37 G. Stem terete; 

 lower internodes shorter than the leaves. Leaves 4 in a verticil, 

 oblong, acute; 4-6 lin. long, f-lj lin. wide, 1-nerved, dentate. Other 

 characters as in the generic description. — Presl. Bot. Bemerk. 112; 

 Engl. Pfl. Ost-Afr. C. 95. Serpiculci verticillata, Roxb. Corom. PI. t. 164. 



wile Xiand. British East Africa : Buddu (ex Engler). 



XVXozaxnb. Dlst. German East Africa : Karagwe, Bukoba (ex Angler). 



Var. /3. hrevifoUa, Casp. in Pringsh. Jahrb. i. 415. Lower internodes much longer 

 than the leaves. Leaves ovate or ovate oblong, 2-3 lin. long, 1-lf lin. wide. Baker 

 in Trans. Linn. Soc. xxix. 152 ; Engl. Pfl. Ost-Afr. C. 95. 



Hile Iiand. Sources of the Nile, 2° N., SpeJce and Grant ! 



2. LAGAROSIPHON, Harv. ; Benth. et Hook. f. Gen. PI. iii. 450. 



Spathes unisexual. Male ovate, 2-fid at the apex, many-flowered. 

 Calyx 3-lobed ; lobes narrow. Petals 3, ovate. Stamens 3 ; anthers 

 ovate. Staminodes often 2-3. Female narrowly oblong, 1-flowered. 

 Calyx and corolla similar to those of the male. Ovary 1 -celled, 

 shortly rostrate, with 3 parietal placentas; styles 3, erect; ovules 

 many, orthotropous. — Stems elongated, branched, clothed ail over 

 with leaves. Leaves alternate, subopposite or (in L. hydrilloides) 

 whorled, linear or linear lanceolate. Spathes axillary, solitary. 



One species extends to South Africa, another is confined to the Mascarene Island?, 

 and a third to India. 



Female spathe entire or nearly so. 



Leaf with 26-33 teeth. Petals lanceolate . . . \. L. Ngassce. 



Leaf with 30 teeth. Petals ovate . . . . 2. L. rubella. 



Leaf with 51-59 teeth. $ spathe with 2-3 teeth at 



the side 3. i. ScTiweinfurthii. 



Leaf with 81-87 teeth. $ spathe without teeth . . 4. X. Steudneri. 



Female spathe bifid. 



Leaves alternate or subopposite. 



Leaves 4^5 lin. long, setaceous. 5 spathe not dentate 

 at the sides . . . . . . . 5. i. tenuis. 



Leaves 6 lin. long, setaceous. ? spathe dentate at 



the sides . . . . . . . . 6. i. muscoides. 



Leaves 6-7 lin. long, ^ lin. broad, 3-nerved . . 7. X. crispus. 

 Leaves 6-11 lin. long, \ lin. broad, l-nerved . . 8. X. cordofanus. 

 Imperfectly known species . , . . , 9. X. Fischeri. 

 Leaves verticillate 10. X. hydrilloideis. 



