The Growth-Forms of Natal Plants. 
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Examples : Scolojpia zeyheri, Kiggelaria africana, Calodendron capense, 
Xanthoxylon capense, Ukehergia capensis, Ilex capensis, Celastrns peduncu- 
laris, Nuxia congesta, Apodytes dimidiata, Cussonia spicata. 
(3) The DEGREE OF PUBESCENCE varies greatly in the same species and 
in different species. 
(4) A DECIDUOUS TENDENCY is Seen in Commiphora caryaefolia, Schmi- 
delia melanocarpa, Bersama tysoniana, Albizzia fastigiata, Celtis hratissiana, 
Zizyphus mucronata, Fteroxylon utile, Rhus laevigata, Plectronia mnndii, 
Bauwoffia natalensis, Croton sylvaticus, some of which are almost always 
wholly deciduous, others being irregularly deciduous or semi-deciduous. 
The deciduous tendency is more pronounced inland and at higher altitudes 
than on the coast, as shown by the species, Erythrina caffra, Calodendron 
capense, Cordia caffra, Celtis Jcraussiana, which are deciduous inland, but 
usually more or less evergreen on the coast. 
Some species are evergreen, or semi-deciduous or deciduous, according to 
locality and general environment, apart from proximity to the coast, e.g. 
Trimeria alnifolia, Bkehergia capensis, Elaeodendron croceum, Plectronia 
mundii. Altogether, about 20 per cent, of the species show the deciduous 
tendency to a greater or less extent — a reaction to the adverse environment 
of the dry winter season. 
(5) Spinosity. — The majority of the thorn trees of the Thorn Veld, etc., 
belong to the next class, Microphanerophytes, and the whole question of 
thorn development will be discussed more fully when that group is dealt 
with. Some of the Acacia species with thorns, though included in the next 
class, occasionally exceed 8 metres in height. Several of the taller trees 
included in the above list show a variable amount of thorn development, 
e.g. Scolopia zeyheri, Xanthoxylon thunhergii, Zizyphus mucronata, Scutia 
commersonii, Erythrina caffra. 
(6) A THICK BARK is a feature of a considerable number. It is particularly 
noticeable where the species grow in such situations that they are exposed to 
grass fires, and it doubtless acts as a protection. The following species 
show it : 
Apodytes dimidiata, Trichilia emetica, Bersama tysoniana, Albizzia 
fastigiata, Odina caffra, Pygeum africanum, Cunonia capensis, Eugenia 
cordata, Cussonia spicata, Cussonia umhellifera, Curtisia faginea, Plectronia. 
obovata, Myrsine melanophleus, Sideroxylon inerme, Olea foveolata, Olea 
laurifolia, Bauwolfia natalensis. Commiphora caryaefolia, Ocotea bullata. 
The same feature is characteristic of many included among Micro- 
phanerophytes. 
(7) A FREE DEVELOPMENT OF COPPICE SHOOTS ofteu modifies the original 
growth-form considerably, giving the appearance of an abnormally large 
trunk, or the main stem may die away and become replaced by a cluster of 
coppice stems. 
