1 62 SANTALACEAE 



COLPOON. 



Colpoon compression, Pruimba&t, Cape sumach. A shrub 5 — B feet high, 



with entire, glaucous leaves, small greenish flowers and dark purple fruit. 

 Flowers generally 4-merous, but some of those which terminate the primary 

 axis of the cymose inflorescences are occasionally 5-merous. 



The leaves contain a glucoside Osyritrin and much tannin; they are 

 largely used for tanning leather, hence the colonial name of the shrub Cape 

 sumach. In the northern parts (Transvaal, Bechuanaland, Rhodesia, German 

 South West Africa) occurs the allied species Osyris abyssinica Hochst., which 

 is employed for the same purpose, going under the names of hcn/hdsf and 

 Transvaal sumach. Neither of them is, however, in any way allied to the 

 real sumach, Rhus coriaria, which belongs to the family Anacardiaceae, 

 being largely cultivated in Sicily and other Mediterranean countries. 



Thesium. 



This genus occurs in various parts of the world, comprising over 50 

 species in tropical and over 70 in South Africa. Most of them or probably 

 all are semi-parasites, at any rate in their youth. Their roots produce long thin 

 threads, which attach themselves to the roots of other plants by producing a 

 disc-shaped sucker at the point of contact. 



Thesium strictum (Fig. 80), which is almost devoid of leaves, and Th. 

 euphorbioides with large oval succulent leaves, both fairly frequent in the South 

 West, are 6 — 8 feet high, while most other species do not exceed 1 or 2 feet. 



Thesidium. 



This genus principally differs from Thesium by its dioecious flowers and 

 the succulent fruit, which is a kind of pseudo-drupe with a fleshy basal ring. 



Thesidium fragile is not unfrequent in the Cape Flats, growing on the roots 

 of Metalasia muricata, Chymococca empetroides and probably some other shrubs. 



Grubria. 



Grubbia stricta. This species has a fairly wide distribution within the 

 Cape region but, although evidently adapted to dry localities, it does not 

 occur outside its limits. Shrubby; 2 — 5 feet high; foliage very dull, almost 

 fawn coloured. The fruit when ripe is very conspicuous through its bright 

 red colour and may attract birds, although there does not seem to be anything 

 pulpy or juicy in it. It is a curious form of pseudocarp consisting of a whole 

 inflorescence like a mulberry or pine-apple, but generally carrying only one 

 fully developed seed. (Plate 37, D.) 



Grubbia rosmarinifolia. This shrub, of similar size, is more dependent on 

 moisture and consequently found only in swampy localities of the mountains, 

 flowering in winter. The leaves are narrow lanceolate, but appear to be 

 almost needle-shaped on account of the revolute margins. While the upper 

 epidermis is glabrous, the lower side of the leaf is thickly covered with a 

 whitish wool ; but almost nothing of this woolly surface is visible, for the 

 margins of the leaf are so strongly recurved that they nearly touch each 



