458 



GIL ASCLEPIADACE^E. 



ASCLEPIAS. 



N. OLEANDER. Rose Day-tree. Oleander. Lvs. linear-lanceolate ; rp.squar- 

 rose ; corona flat, its segments 3-toothed. Native in S. Europe and the Levant. 

 Stem branched. Leaves 3 together, on short stalks, smooth, very entire, coria- 

 ceous, with prominent, transverse veins beneath. Flowers terminal, corym- 

 bose, large and beautiful, rose-colored. One variety has white flowers, another 

 variegated, and a third, double. This splendid shrub is common in Palestine, 

 (Rev. S. Hcbard!) growing by rivulets, &c. It is commonly supposed by travel- 

 ers to be the plant to which the Psalmists alludes, Ps. i. 3, and xxxvii. 35. 



ORDER OIL ASCLEPIADACEJE. AscLEriArs. 



Herbs or shrubs, with a milky juice. Lvs. almost constantly opposite, entire, exstipulate. 

 FIs. somewhat umbeled, fascicled or racemose. Sep. 5, slightly united, persistent. 



Cor. petals 5, united at base, regular, deciduous, 

 twisted-imbricate in aestivation. 



Sta. 5, inserted into the base of the corolla and alter- 

 nate with its segments. 



Fil. connate. Anth. 2-celIed, cells sometimes nearly 

 divided by partial septa. 



Pol. when the anther bursts cohering in masses 

 which are as many as the cells, or confluent into 

 pairs and adhering to the 5 processes of the 

 stigma either by 2s, by 4s or singly. 



Ova. 2, styles 2, approximate, often very short. Stiff- 

 mas united into 1, which is common to both 

 styles, and with 5 glandular angles. 



Fr. Follicles 2, one of them sometimes abortive. 



Sds. numerous, pendulous, almost always comose at 

 the hilum. Albumen thin. 



Embryo straight. Cotyledons foliaceous. Radicle 

 superior. 



Genera 141, species 910, chiefly natives of tropical 

 regions, find especially abundant in S. Africa, S. India 

 and New Holland, but are not uncommon in tempe- 

 rate regions. . * 



Properties. Similar to .those of the Apocynaceas, 

 but far less active. The juice is acrid and stimujat- 

 ing, and generally lo be, at least, suspected. A few 

 01 the species are medicinal, but none of much con- 



FIG. 55. 8. Asclepias cornuti. 9. A flower, the 

 petals and sepals reflexed, and the corona erect. 10. 

 One of the segments of the corona with the horn bent 

 inwardly. 11. A pair of pollen masses suspended 

 from the glands at an angle of the antheridium. 12. 

 The two ovaries. 13. A mature follicle. 14. A seed 

 with it c k>ng silky coma. 



Conspectus of the Genera. 



\ each with a horn. 



(erect. Segments of the corona 5, distinct, \ without horns. Fls. greenish. . 

 Corona leaflets 5, distinct, each 2-lobed. FIs. white. 

 Corona annular, undulate, 0-awned. _Fls. purple. 



rple. 



Asclepias. 1 



Acerates. 2 



Enalenia. 3 



Gonolobus. 4 



Periploca. 5 



Herbs I twining and climbing. ( Corona urceolate, 5-cjeft, 5-awned. FIs. pur 



1. ASCLEPIAS. 



The Gr. name, from Esculapius, the fabulous god of medicine and physicians. 



Calyx deeply 5-parted ; cor. deeply 5-parted, valvate in aestivation, 

 finally reflexed ; stamina! corona 3 -leaved, leaflets cucullate, with an 

 averted, horn-like process from the base, curved towards the stigma ; 

 antheridium (connate mass of anthers) 5-angled, truncate, opening 

 by 5 longitudinal fissures ; pollinia (masses of pollen) 5 distinct 

 pairs, fixed by the attenuated apex, pendulous ; follicles 2, ventri- 

 cose ; seeds comose. % Mostly North American, with opposite, verti 

 dilate, rarely alternate leaves. Umbels between the petioles. 



* Leaves opposite. 



1. A. CORNUTI. Decaisne. (A. Syriaca. Linn, and 1st edit.') Common Silk 



weed. St. simple; Ivs. oblong-lanceolate, petiolate, gradually acute, 



tomentose beneath; umbels noddfng; seg. of the corma bidentate; follicles rnuri- 



rate. A coarse, very lactescent plant, common by roadsides, and in sandy 



