Chap. V] TROPICAL DISTRICTS WITH DRY SEASONS 369 



(Tricholaena, Setaria, Pennisetum), Agrostideae (Sporobolus, Aristida gracillima), 

 Chlorideae (Enteropogon, Chloris, Leptochloa, Lepidopironia), Aveneae (Tristachya, 

 Trichopteryx), Festuceae (Eragrostis). The subordinate herbs growing among the 

 grasses are ' partly bulbous or rhizomatous plants with solitary flowering shoots, 

 partly herbaceous perennials that form a short low stock and send up a tuft of 

 flowering shoots.' Herbaceous Monocotyledones are not numerous. Engler 

 specially mentions Aneilema Johnstonii, Commelina bracteosa, Chlorophytum 

 macrophyllum and C. tuberosum, Gloriosa virescens, also some species of Scilla, 

 Asparagus, some Amaryllidaceae (Haemanthus, Hypoxis), Iridaceae (Acidanthera), 

 Orchidaceae (Lissochilus, Habenaria). Among Dicotyledones, greyish-green 

 Amaranthaceae, not unfrequently 1-2 meters high, take a prominent place ; they 

 belong chiefly to Celosia, Digera, Sericocomopsis, Pupalia, Aerva, Achyranthes, 

 Nothosaerva. The Nyctaginaceae are represented by the common weed Boer- 

 haavia diffusa, the Aizoaceae rather weakly by Trianthema pentandrum and Glinus 

 lotoides, the Phytolaccaceae by two annual succulent herbs, Limeum viscosum and 

 Giesekia pharnaceoides. Talinum patens, a succulent weed belonging to the Portu- 

 lacaceae, is common. The Cruciferae are very scanty (two species of Farsetia). 

 A strong contingent comes from the Papilionaceae, especially species of Indigofera and 

 Tephrosia, besides several Hedysareae (Zornia, Stylosanthes, Desmodium, Pseudar- 

 thria), Phaseoleae (Rhynchosia, Eriosema), and many others. The Caesalpiniaceae are 

 poorly represented by a few Cassieae. Species of Polygala, Malvaceae, and Sterculia- 

 ceae are fairly numerous. The Euphorbiaceae are few, and there are no Umbelliferae. 

 Among the Gamopetalae, Asclepiadaceae (Gomphocarpus, Stathmostelma, Schizo- 

 glossum) and Convolvulaceae (Convolvulus, Ipomoea, especially Astrochlaena) play 

 a prominent part by their abundance and by their large flowers. Labiatae are also 

 numerous (especially species of Leucas), but the most numerous of all Dicotyledones 

 are Acanthaceae (especially species of Justicia, Barleria, Blepharis capensis, Neur- 

 acanthus scaber). The family of Compositae, which is so richly developed in the 

 South American prairie, is poor in forms in the South African, and is limited to 

 species belonging to Vernonieae and Inuleae. The following families also 

 supply representatives of subordinate import : Gentianaceae (Enicostemma verti- 

 cillatum), Boraginaceae (species of Heliotropium), Verbenaceae (Leptostachys), 

 Scrophulariaceae (Striga, Scoparia), Solanaceae (Solanum), Cucurbitaceae 

 (Corallocarpus, Cucumis), Passifloraceae (Tryphostemma, Adenia), and Rubiaceae 

 (Oldenlandia). 



Engler's bush-grass-steppe, a shrub-savannah according to our terminology, 

 contains singly, or in small groups, various kinds of shrubs. The following are 

 represented : Anonaceae (Anona senegalensis), Capparidaceae (Capparis, Courbonia, 

 Cadaba, Maerua, Thylachium), Leguminosae (Acacia, Diphaca), Malpighiaceae (Di- 

 aspis albida, Triaspis auriculata), Euphorbiaceae (species of Phyllanthus, Bridelia, 

 Acalypha, Flueggea), Anacardiaceae (Rhus villosa, R. glaucescens), Celastraceae 

 (Gymnosporia senegalensis), Sapindaceae (Deinbollia borbonica), Rhamnaceae 

 (Zizyphus Jujuba), Thymelaeaceae (Gnidia), Verbenaceae (Bouchea pterygocarpa), 

 Acanthaceae (Blechum hamatum, Hygrophila Volkensii), Rubiaceae (Crossopteryx 

 africana, Gardenia Thunbergiij. 



The trees in Engler's tree-grass-steppe, a real savannah according to our 

 terminology, are chiefly species of Acacia (A. subulata, A. Seyal, A. spirocarpa, 



SCHIMPER ]J t) 



