EUPHORBIACE^E 373 



in that the flowers occur in clusters of three, the 

 middle one only being fertile, while the sepals of 

 the two others form strong hooked spines by which 

 the whole cluster may fasten on the fur of animals, 

 (p. 263). 



EUPHORBIACE^: 



Examples : 



RICINUS COMMUNIS, L. the Castor-oil plant, an 

 annual herb or shrub, in some varieties red in others 

 green, and sometimes with a bluish-white (glaucous) 

 powdery substance on the stems and petioles. 



Leaves alternate, and covered completely in bud by 

 the large stipules, which falling off leave a scar ex- 

 tending right round the stem. Petiole with large glands 

 on either side at the base and near the blade. Blade 

 peltate, orbicular, palmately lobed; the lobes serrate, 

 membranous, glabrous. 



Flowers in thyrsoid panicles, unisexual and monoe- 

 cious, the upper flowers with stamens only, the lower 

 with ovary only. Staminate flowers with three to five 

 valvate sepals, no petals, but numerous stamens with 

 branched filaments and distinct round anther cells ; 

 no ovary. Ovary flowers with calyx which falls off, 

 no petals, no stamens, and a three-celled ovary with 

 three styles; and in each cell one pendulous ovule 

 attached at its top end to the inner angle. Fruit a 

 capsule dividing into three parts, each splitting open 

 and setting free its seed. Seed oblong with hard 

 testa, symmetrically marked on the rounded side, and 

 having a whitish soft caruncle covering the micropyle 



