Crassulaceae, Saxifragaceae 55 



sometimes thickened, usually with 00 ovules. — Most of 

 the families of this order are very difficult to demarcate. 



Suborder i. Saxifragineae. Carpels as many as 

 petals or fewer. Endosperm mostly copious (scanty in 

 Crassulaceae). 



Fam. I. Crassulaceae. Mostly succulent herbs. 

 Leaves exstipulate. Flowers cyclic, heterochlamydeous, 

 3-30-merous, haplo- or obdiplostemonous, mostly her- 

 maphrodite and actinomorphic. Petals free or united. 

 Carpels usually isomerous, free or slightly coherent, with 

 glandular scales at base. Ovules mostly 2-seriate on the 

 ventral suture. Fruit of follicles. Seeds small oblong 

 with scanty endosperm. 



A. Obdiplostemonous. 

 * Petals free. 



Leaves scattered or 2-3 in a whorl. Flowers 4-5- 

 merous. Sedum. 



Leaves rosulate. Flowers 6-20-merous. 



*Sempervivum. 

 ** Corolla tubular, 5-lobed. Cotyledon. 



B. Haplostemonous. 



Leaves opposite. Flowers 3-5-merous. 



Crassula (including Tillaea). 



Fam. 2. Saxifragaceae. Mostly herbs. Leaves 

 usually spiral. Stiptdes absent or present as outgrowths 

 from the leaf-sheath. Flowers cyclic, usually hetero- 

 chlamydeous and 5-merous (but Carpels mostly oligo- 

 merous), hermaphrodite, actinomorphic. Floiver-axis 

 convex, flat, or concave, in the latter case usually united 

 by its whole length to the carpels. Stamens usually 



