232 94- HYDROST ACH YACEAE — 95. CRASSULACEAE 



anther-halves (or 2 with united filaments)., hypogynous. Anthers turned 

 outwards. Pollen-grains united in groups of 4. Ovary i-celled, with 2 parietal 

 placentas. Ovules numerous, inverted. Styles 2. Fruit capsular. Seeds 

 exalbuminous. (Under PODOSTEMONACEAE.) (Plate 58.) 

 Genus i, species 15. Tropical and South-east Africa. 



Hydrostachys Thouars 



SUBORDER SAXIFRAGINEAE 



FAMILY 95. CRASSULACEAE 



Herbs or undershrubs, rarely shrubs. Stem and leaves usually succulent. 

 Leaves without stipules. Flowers regular, hermaphrodite. Petals 3 — 20, 

 free or imited below, hypogynous or nearly so. Stamens as man\' or twice as 

 many as the petals. Filaments free. Anthers turned inwards. Carpels as 

 many as the petals, free or united at the base, usually with a scale-like append- 

 age. Ovules numerous, rarely {Crassula) i — 2 in each carpel. Fruit-carpels 

 follicular. Seeds with a very scanty albumen or without albumen. — Genera 

 10, species 400. (Plate 59.) 



1. Petals free or nearly so 2 



Petals united below into a distinct, usually long tube 5 



2. Stamens as many as the sepals or petals, 3 — 9, usually 5. Sepals free or 



nearly so. Petals white or reddish. Leaves opposite. — Species 180. 

 Some of them are used as ornamental or medicinal plants. (Including 

 Bidliarda DC, Dinacria Harv., Helophytum Eckl. & Zeyh., and Tillaea 



L.) Crassula L. 



Stamens twice as many as the sepals, rarely {Sedum) equalling the sepals in 

 number, but then leaves alternate 3 



3. Flowers 4 — 5-merous, very rarely 6 — 7-merous. Sepals free or nearly 



so. Leaves usually scattered. — Species 25. North Africa and high 

 mountains of East Africa. Some species are used as vegetables or as 



medicinal or ornamental plants Sedum L. 



Flowers 6 — 20-merous, very rarely 5-merous. Sepals more or less united. 

 Leaves usually rosulate 4 



4. Scale-like appendages of the carpels broad, petaloid. Petals linear- 



lanceolate, inconspicuous, reddish or yellowish. — Species 10. North- 

 west Africa. {Peirophyes Webb) Monanthes Haw. 



Scale-hke appendages of the carpels small or wanting. Petals lanceolate, 

 brightly coloured. — Species 70. North Africa and northern Central 

 Africa. Some are used as ornamental or medicinal plants. " House- 

 leek." (Including Aeonium Webb, Aichryson Webb, and Greenovia 

 Webb <t Berth.) Sempervivum L. 



5. Flowers 4-merous. Leaves opposite 6 



Flowers 5 — 6-merous S 



