CRASSULACEAE. 183 



rarely wanting; stamens of the same number or twice as many 

 as the petals; carpels of the same number as the sepals, distinct 

 or united below; ovules numerous; follicles 1-celled; seeds minute; 

 endosperm fleshy. 



Flowers solitary axillary; annuals. 242. TILLAEA, 183. 

 Flowers cymose; perennials or biennials. 



Petals free to the base. 243. SEDUM, 183. 



Petals united below the middle. 244. GORMANIA, 184. 



242. TILLAEA. 



Small and slender somewhat succulent glabrous annual herbs; 

 leaves opposite, entire; flowers minute, solitary axillary, white; 

 sepals and petals 3-5, distinct or united at the base; stamens as 

 many as the petals; carpels distinct; styles short-subulate; 

 ovules 1-many. 



Tillaea aquatica L. (T. angustifolia Nutt.) Stems branching, rooting at 

 base, 2-5 cm. high; leaves linear, acute, the pairs somewhat connate; flowers 

 mostly solitary, nearly sessile; petals ovate, obtuse, twice as long as the sepals; 

 carpels obtuse; seeds many, oblong-linear. 



On muddy river banks, rare. 



243. SEDUM. STONECROP. 



Fleshy mostly glabrous herbs, erect or decumbent; leaves 

 alternate, entire or dentate, fleshy; flowers perfect, in terminal 

 often 1-sided cymes; calyx 4 or 5-lobed or parted; petals 4 or 5, 

 distinct; stamens 8 or 10, perigynous, the alternate ones usually 

 attached to the petals ; carpels 4 or 5 , distinct or united at the base ; 

 ovules numerous; follicles few-many-seeded. 



Leaves spatulate, very glaucous. S. spaihulifolium. 

 Leaves not spatulate nor glaucous. 



Leaves subglobose. 5. divergent. 

 Leaves lanceolate, broadest at base. 



Leaves becoming scarious; carpels divergent. S. douglasii. 



Leaves not becoming scarious; carpels erect. S. stenopetalum. 



Sedum spathulifolium Hook. Herbage very glaucous; stems decumbent, 

 10-20 cm. long, curved upward near the tips; leaves broadly spatulate, flat, 

 15-20 mm. long; flowers pale yellow, nearly sessile, in a rather compact com- 

 pound cyme; petals lanceolate, acute, 6 mm. long, much longer than the sepals. 



On rocks, common. 



Sedum divergens Wats. Glabrous and bright green; stems decumbent, 

 5-10 cm. long; leaves oval in outline, subglobose, nearly as thick as broad, 

 sessile, 7-8 mm. long, mostly in rosettes at the ends of the branches; flowers 

 yellow, in a compact cyme; petals three times as long as the sepals; carpels 

 widely divergent when mature. 



In the mountains at moderate elevations. 



Sedum douglasii Hook. Stems erect, branched at base, from a stout 

 rootstock, 15-20 cm. high; leaves lanceolate, attenuate at the apex, 6-12 mm. 



