164. 



CRASSULACEAE. 



Carpels distinct to the base; plants very succulent. 



Stamens of the same number as the sepals; minute herbs. 

 Stamens twice as many as the sepals; succulent herbs. 

 Flowers 4-5-parted. 

 Flowers 6-i2-parted. 

 Carpels united to about the middle; plant scarcely succulent. 



[VOL. II. 



1. Tillaea. 



2. Sedum. 



3. Sempervivum. 



4. Penthorum. 



i. TILLAEA L. Sp. PI. 128. 1753. 



Minute, mostly glabrous, aquatic or mud-loving succulent herbs, with opposite entire 

 leaves and very small solitary or cymose-paniculate axillary or terminal flowers. Calyx 

 3-5-parted. Petals 3-5, distinct, or united at the base. Stamens 3-5. Carpels 3-5, distinct. 

 Styles short, subulate. Ovules usually few. Follicles few-seeded or several -seeded. 

 [Named after Michael Angelo Tilli, 1653-1740, an Italian botanist] 



About 20 species, of very wide geographic distribution. 

 occur in the western and southwestern States. 



Besides the following, about 4 others 



i. Tillaea aquatica L. Pigmy-weed. (Fig. 1809.) 



Tillaea aquatica L. Sp. PI. 128. 1753. 



Tillaea simplex Nutt. Journ. Acad. Phil, i: 114. 1^17. 



Rulliarda aquatica DC. Prodr. 3: 382. 1828. 



Stem ascending or erect, usually simple, l A'-z' high, 

 glabrous. Leaves linear-oblong, entire, acutish or obtuse 

 at the apex, connate at the base, 2"-3" long, at length 

 shorter than the internodes; flowers solitary, axillary, ses- 

 sile or short-peduncled, W broad; calyx-lobes, petals, 

 stamens and carpels 4, rarely 3; petals greenish, about 

 twice the length of the calyx-lobes; follicles ovoid, longer 

 than the calyx-lobes, 8-io-seeded. 



Muddy banks of streams, Nova Scotia to Massachusetts and 

 Maryland, near the coast. Stem often rooting at the nodes. 

 Also in Europe. July-Sept. 



2. SEDUM L. Sp. PI. 430. 1753. 



Fleshy mostly glabrous herbs, erect or decumbent, mainly with alternate, often imbricated, 

 entire or dentate leaves, and perfect or dioecious flowers in terminal often i -sided cymes. 

 Calyx 4-5-lobed. Petals 4-5, distinct. Stamens 8-10, perigynous, the alternate ones usually 

 attached to the petals. Filaments filiform or subulate. Scales of the receptacle entire or 

 emarginate. Carpels 4-5, distinct, or united at the base; styles usually short; ovules oo . 

 Follicles many-seeded or few -seeded. [Latin, to sit, from the lowly habit of these plants.] 



About 150 species, mostly natives of temperate and cold regions of the northern hemisphere, a 

 few in the mountains of Mexico and the Andes of South America. Besides the following, about 

 jo others occur in the western parts of North America. 



Cyme regular, compound, the flowers not secund; leaves broad, flat. 



Flowers dioecious, mostly 4-parted. i. 5. roseum. 



Flowers perfect, 5-parted. 



Petals purple; plant somewhat glaucous; petals twice as long as the sepals. 



2. S. Telephium. 



Petals pink; plant very glaucous; petals 3-4 times as long as the sepals. 3. S. telephioides. 

 Flowers secund along the branches of the cyme. 

 Petals yellow. 



Leaves short, thick, ovate, densely imbricated. 4. S. acre. 



Leaves linear or terete, scattered on the stems. 



Annual; petals little longer than the sepals. 5. S. Torreyi. 



Perennial ; petals twice as long as the sepals. 



Plant 3' -6' high; native, western. 6. S. stenopetalum. 



Plant 8'-i2' high; introduced in a few places. 7. S. reflexum. 



Petals purple or white. 



Leaves terete; petals purple, pink, or white. 8. 5. pulchellum. 



Leaves flat, spatulate or obovate; petals white. 



Lower leaves verticillate in 3's. 9. 5. fenialtini. 



Leaves all alternate. 10. 5". Nevii. 



