CXVI. PODOSTEMACEiE. 851 



bearing half an anther that bursts outwardly. — Female : 

 Ovary minute, plano-convex ; stigmas 2, filiform ; ovules nu- 

 merous, on 2 parietal placentas. Capsule bursting by 1 longi- 

 tudinal slit. JSeeds very minute. — Tulasne^ Monog. Fodoniem. 

 p. 47. 



Perennial, stemless water-plants, growing on stones, natives chiefly of Ma- 

 dagascar. Leaves few, very long, simple or compound, often covered with 

 appendages. Scapes long, naked or scaly below, above covered with im- 

 bricating floriferous bracts. — 1 species, from Natal, apparently identical 

 with a Madagascar one {U. imbricata). 



2. SPHJEROTHYLAX, Bischoff. 



Elowers hermaphrodite, at first sessile in a spathe, which 

 bursts irregularly, finally exserted on a pedicel. Perianth 0. 

 Stamens 2, monadelphous, with 2 lateral staminodia ; filament 

 of the fertile stamens united to the middle ; anthers 2-lobed, 

 bursting inwardly. Ovary oblique, 1-celled ; stigmas 2, free, 

 short, linear ; ovules very numerous, on a thick central pla- 

 centa. Capsule ribbed, 2-valved, very many-seeded. — Talasne, 

 Monog. Podostem. p. IGO. 



A small, creeping, almost leafless plant, forming ?raall, green expansions 

 (fronds) on stones under water, which consist of much-branched, interlacing, 

 linear lobes. Spathes sessile on the fronds. — Only 1 species known, from 

 Natal. 



3. TRISTICHA, Petit Thenars. 



Flowers hermaphrodite. Perianth membranous, 3-parted. 

 Stamen 1 ; anthers ovate, 2-celled, bursting inwardly. Ovary 

 shortly stalked, 3-celled ; stigmas 3, short, linear ; ovules very 

 numerous, in the angles of the cells, on very thick placentas. 

 Capsule 3-gonous, 9-ribbed, 3-celled, 3-valved, many-seeded. 

 — Tidasne, Monog. Podosteni. p. 179. 



African and American submerged, moss-like plants. Stems elendcr, 

 branched. Leaves small, ovate, entire, crowded, scattered or whorled. 

 Flowers axillary or terminal, solitary or crowded. — 2 species, from Natal. 



Subclass 2. GYMNOSPEBMyK 



Order CXYII. GNETACEiE. 



Flowers in monoecious or dioecious catkins, accompanied by 

 torn sheaths or palea% the male girt with a 2-fid sheath. 

 Stamens 1 or more, connate at base or in a colunni ; anthers 

 2-4-celled ; cells opening by an oblong pore. Ovules ses- 

 sile, erect, orthotropous, with a single, double or triple coat, 

 the outer coat opening by a narrow mouth, the iinier produced 



