201. ASCLEPIADACEAE — 202. CON VOLVULACEAE 457 



small. Leaves linear. — Species i. Southern West Africa (Amboland). 



Craterostemma K. Schura. 

 Outer corona divided into lo lobes. Flowers usually fascicled. . . .117 



117. Corolla rotate, with valvate aestivation. Stem branched. Flowers 



small. — Species 2. South Africa. (Under Anisotome Fenzl or Bra- 



chystelma R. Br.) Decaceras Harv. 



Corolla rotate-campanulate, with contorted aestivation. Stem simple. — 

 Species 5. South and East Africa. (Under Brachystelma R. Br. or 

 Tenaris E. Mey.) Lasiostelma Benth. 



118. Outer corona-lobes 5, entire or 2-cleft 119 



Outer corona-lobes 10, free from each other or nearly so. Pollen-masses 



disciform. Flowers solitary, fascicled, or umbellate 123 



119. Corolla campanulate. Roots spindle-shaped. Stem erect. Flowers solit- 



ary or fascicled. — Species 6. South Africa. (Under Brachystelma R. 



Br., Dichaelia Harv., or Lasiostelma Benth.) Brachystelmaria Schlecht. 



Corolla rotate. Roots fibrous, somewhat fleshy 120 



120. Stem erect, arising from a tuber. Leaves linear. Flowers usually in 



racemes or panicles, rather large. Corolla-segments linear. Anthers 

 usually with a short appendage at the apex. — Species 5. Central and 



South Africa Tenaris E. Mey. 



Stem prostrate or twining. Leaves oblong or ovate. Flowers solitary 

 or in fascicles or pseudo-umbels. Anthers without an appendage. . 121 



121. Leaves ovate. Flowers solitary or in pairs, small. Corolla yellow, with 



ovate segments. Stem prostrate, springing from a tuber. — Species i. 



South Africa. (Under Brachystelma R. Br.) Tapeinostelma Schlecht. 



Leaves cordate. Flowers in fascicles or pseudo-umbels 122 



122. Stem prostrate. Flowers small. Corolla-segments oblong-linear. Inner 



corona-lobes subulate. — Species 2. South Africa. {Lophostephus 



Harv.) Anisotome Fenzl 



Stem twining. Inner corona-lobes oblong or linear-oblong. — Species 2. 

 South Africa Emplectanthus N. E. Brown 



123. Outer corona-lobes erect. Corolla-segments cohering at the tip. — Species 



15. South Africa. (Under Brachystelma R. Br.) Dichaelia Harv. 



Outer corona-lobes spreading. Corolla-segments free at the tip. — 



Species 35. South and Central Africa. Some have edible tubers. 



(Including Micraster Harv.) Brachystelma R. Br. 



ORDER TUBIFLORAE 



SUBORDER CONVOLVULINEAE 



FAMILY 202. CONVOLVULACEAE 



Leaves alternate, simple, sometimes dissected or reduced to scales, exstipulate, 

 rarely {Ipomoea) stipulate Flowers regular, rarely slightly irregular, usually 

 hermaphrodite. Sepals 5, rarely 4, persistent. Petals united into a 5-angled, 

 5-lobed, or 5-cleft, rarely a 4-lobed corolla, usually with plicate-valvate aestiva- 



