200. APOCYNACEAE — 201. ASCLEPIADACEAE 44I 



margin at the base. Small trees. Leaves opposite. Flowers in 

 terminal, many-flowered panicles. — Species i. Madagascar. 



Stephanostegia Baill. 

 Corolla without a ring, but sometimes with a crown of hairs at the throat. 58 



58. Corolla-lobes overlapping to the right Calyx-segments narrow. Stamens 



inserted in the lower part of the corolla-tube. Seeds with an apical 

 tuft of hairs. Trees or erect shrubs. Leaves opposite, herbaceous, 

 cxstipulate. — Species 6. Tropics. Some of them yield timber or 



medicaments Holarrhena R.Br. 



Corolla-lobes overlapping to the left 59 



59. Stamens inserted at the base of the corolla-tube. Anthers with short, 



pointed tails at the base. Twining shrubs. Leaves opposite, stipulate. 



without axillary glands. (See 46.) .... Gabunia K. Schum, 



Stamens inserted at the middle or in the upper part of the corolla-tube. 



Anthers not tailed 60 



60. Stamens inserted about the middle of the corolla-tube. Anthers acuminate. 



Stigmatic head elliptical. Seeds winged. Twining shrubs. Leaves 

 opposite. Flowers in lateral, few-flowered cymes. — Species 2. Mada- 

 gascar and Comoro Islands Ellertonia Wight 



Stamens inserted in the upper part of the corolla-tube. Erect shrubs. 

 Leaves whorled. Flowers in terminal cymes or panicles 61 



^i. Ovules in two rows. Corolla yellow, glabrous at the throat ; lobes auricled 

 at the base. Seeds winged. Leaves with few or obscure side-nerves. 

 Flowers in few-flowered cymes. — Species i. South Africa. Yields 



timber and an aromatic oil Gonioma E. Mey. 



Ovules in 3 or more rows. Seeds hairy. Leaves with numerous side- 

 nerves. Flowers in many-flowered, whorled panicles. — Species i. 

 Central Africa. Poisonous and yielding cork-wood, a guttapercha-like 

 resin, and medicaments Alstonia R. Br. 



FAMILY 201. ASCLEPIADACEAE 



Stem usually twining and woody at the base. Juice mostly milky. Leaves 

 simple, without stipules, usually opposite, sometimes reduced to scales. Flowers 

 with bracts and bracteoles, regular, hermaphrodite, 5-merous. Sepals free or 

 nearly so, imbricate in bud. Petals united below, with contorted or valvate 

 aestivation. Stamens 5, usually adnate to the style. Filaments short or 

 wanting. Pollen-grains united in waxy masses or in granules of 3 — 5 grains. 

 Corona formed of appendages of the petals or stamens, rarely wanting. Disc 

 none. Ovaries 2, free, superior, rarely half-inferior, with many pendulous 

 inverted ovules on a ventral placenta, very rarely {Emicncarpiis) with i — 2 

 ovules. Styles 2, united above into a thickened, sometimes 2-parted head 

 bearing on its under surface 5 stigmatic dots and on its flanks between the 

 anthers 5 small, usually horny bodies (" pollen-carriers ") to which the pollen is 



