Classification of Plants 285 



Quercus (the Oak) and Castanea (the Chestnut) repre- 

 sent the two genera of this order which have been introduced 

 into South Africa. 



Order PROTEACE^E. 



The Proteaceae, the glory of the Cape, are found also in 

 Australia, New Zealand, Eastern Asia, the mountains of Tropical 

 Africa, as well as in South America. Most of the plants of 

 this order live in regions where there are long dry seasons 

 alternating with rainy periods, and since they are neither suc- 

 culent nor bulbous plants, their xerophytic habit is shown in 



their leaves. These meet their need of preventing transpira- 

 tion in such a variety of ways that the order has received its 

 name from the mythical sea-god Proteus, who delighted in a 

 constant change of form. 



A reduction of the leaf surface is a simple mode of preventing trans- 

 piration. Australian Hakea (used for hedges), Serruria, and Protea rosacea, 

 Linn., adopt this plan. Protea cynaroides, Linn., has broad leaves, but 

 they are protected by a thick leathery cuticle. The coating of hairs on 

 the silver leaves have a similar use and, like all white surfaces, reflect the 



