3U 



CRASSULACE^. 



[Hypogynous Exogens. 



Order CXX. CRASSULACEiE.— House-leeks. 



Sempemvae, Juss. Gen. 207. (1789).— Succulents;, Vent. Tabl. 3. 271. (1799).— Crassulas, Juss. Did. des 

 Sc. Nat. 11. 369. (1818).— Crassulacese, DC. Bull. Philom. n. 49. p. 1. (1801; ; Fl. Fr. cd. 3. v. 4. p. 

 271. (1805) ; Memoire (1828) ; Prodr. 3. 381. (1828) ; Endl. Gen. clix. ; Meisn. p. 134.— Sedeae, 

 Spreng. 



Diagnosis. — Violal Exogens, loiili polypetalous or monopetaloiLS jloioers, a many-leaved 

 calyx, hypogynous petals, and follicular apocarpous fruit. 



Succulent herbs or shrubs. Leaves entire or pinnatiiid ; stipules none. Flowers 

 usually in c;yTnes, sessile, often arranged on one side only, along the divisions of the 

 cymes. Sepals from 

 3 to 20, more or less 

 united at the base. 

 Petals inserted in 

 the bottom of the 

 calyx, either dis- 

 tinct or coheinng in 

 a monopetalous co- 

 rolla. Stamens in- 

 serted with the pe- 

 tals, either equal 

 to them in number 

 and alternate with 

 them, or twice as 

 many, those oppo- 

 site the petals being 

 shortest, and arriv- 

 ing at perfection 

 after the others ; 

 filaments distinct, 

 subulate ; anthers 

 of 2 cells, bui'sting 

 lengthmse. Hj-po- 

 g}Tious scales seve- 

 ral, 1 at the base of 

 each carpel, some- 

 times obsolete. Car- 

 pels of the same 

 number as the pe- 

 tals, opposite to 

 which they are 

 placed aroimd an 

 imaginary axis, 1- 



celled, tapermg into stigmas, sometimes consohdated ; 

 styles continuous with the ovaries ; o\Tiles sutural, 00, 

 or definite in number, horizontal or pendulous, anatro- 

 pal. Fruit consisting of several follicles, opening by 

 the sutm'e, or collected into a capsule of several cells 

 opening at the back. Seeds attached to the margins of 

 the suture, variable in number ; embryo straight, in the 

 axis of fleshy albumen, with the radicle pointing to the hUum. 



All these plants are remarkable for the succulent nature of their stems and leaves, in 

 which they resemble many other and very different Orders, De Candolle suggests that 

 their real affinity is with Saxifrages tln-ough Penthorum, and with Knotworts (Illecebracece) 

 tlirough Tillsea. In both those Orders the hypogynous scales of Houseleeks are wanting. 



Fig. CCXXXVI. 



Fig. CCXXXVII. 



Fig, CCXXXVI.— Sedum acre. 



Fig. CCXXXVII.— 1. its flower j 2. its seed cut open. 



