DESCRIPTION:--_Branches_ succulent. _Leaves_ up to 5 cm. long, 3 cm. broad, obovate, rounded at the apex, produced into a short broad petiole, articulated to the branches, glabrous. _Inflorescence_ terminal, in large lax cymose panicles. _Calyx_ campanulate, with very short lobes. _Petals_ 1 cm. long, 2·5 mm. broad, oblong, with a small apiculus at the apex. _Stamens_ 5, alternating with the petals; filaments 5·5 mm. long, linear, tapering upwards; anthers more or less crescent-shaped. _Hypogynous glands_ oblong, rounded above. _Carpels_ 5, free; ovary ellipsoid; style 3 mm. long, terete; stigma small, capitate. * * * * * PLATE 156.--Fig. 1, median longitudinal section of flower; Fig. 2, a single carpel; Fig. 3, stamen; Fig. 4, hypogynous gland. F.P.S.A., 1924. [Illustration: _157._] PLATE 157. EUPHORBIA COOPERI. _Natal and Transvaal._ * * * * * EUPHORBIACEAE. Tribe EUPHORBIEAE. EUPHORBIA, _Linn._; _Benth. et Hook. f. Gen. Plant._ vol. iii. p. 258. * * * * * =Euphorbia Cooperi=, _N.E. Br. ex Berger, Sukk. Euphorb._ 83 and 84, Fig. 21; _Fl. Cap._ vol. v. sect. 2, p. 368. * * * * * The genus _Euphorbia_ is represented in South Africa by one hundred and eighty-three species, and we figure a representative of this genus for the first time. The genus contains many species which are of economic value as stock-food plants in the drier parts of the country, and among these may be mentioned _E. esculenta_, Marl. (Vingerpol), _E. brachiata_, E. Mey. (Soet or Blou Melkbos), _E. coerulescens_, Haw. (Soet Noorsdoring), and several other species which are commonly known as “Noorsdoring.” The species figured here is one of the arborescent members of the family, and is found in Natal and in the Rustenburg and Piet Potgieter’s Rust Districts of the Transvaal. It is easily recognised by the continuous horny margins on the stems. The plant when cut exudes a copious milky juice, which is a skin irritant, and which also causes a burning sensation in the throat if the air is inhaled when standing in close proximity to a bleeding plant. Our plate was prepared from a plant growing at the Division of Botany, Pretoria.