294 .1. w. EEWS. 



tion. Where tlie sand has been partially fixed by the latter, 

 or where it is harder packed and not shifting-, the Ipomgea 

 creeps over it rather than throngh it. But it frequently also 

 becomes buried, as is shown in Plate XIY, fig. 1. In this 

 association a grass commonly occurs, but I have not been 

 able to obtain it in flower. 



3. Mbsembryanthemum Association. — Mesembry ant he- 

 mum sp. (edule?) often covers the sand completely and 

 grows rather over it than through it. It forms a dense green 

 succulent covering just below the bush. Sometimes it 

 is more straggling, and is found mixed with the Ipom^ea. 



Near the upper limits of these associations where they grade 

 into the coast bush the following plants are found^ : 



Gazania uniflora^ Cynanchium obtusif olium, C. 

 natalitium, Brachylasna discolor, Cryptostemma 



niveum, Passerina ericoides, Samolus porosus, 



Osteospermum moniliferum, Helichrysum tereti- 



f o 1 i u m , T e p h r o s i a c a n e s c e n s , H y d r o p h y 1 a X c a r n o s a . 

 In certain places, as at Isipingo and Park Rynie, the belt of 



shifting sand nearest to the sea is interrupted by rocks. 



These rocks are surrounded and sometimes half-covered by 



the sand, and they have the sand-dune bush behind them. 



There are no stretches of beach gravel. On the rocks at 



Isipingo the following plants are found : 



Grazania uniflora, Dimorphotheca fruticosa, Sali- 



cornia herbacea, Passerina sp., Helichrysum tereti- 



folium, Carissa grandiflora. 



(2) PSAMMOPHILOUS BUSH FORMATION. 



Here the sand-dunes have become entirely fixed, and 

 remain so unless the bush is interfered with and destroyed. 

 The height of the dunes themselves is from 50 to "200 feet. 



' In this and subsequent lists the commoner or more characteristic 

 plants are mentioned first, and quite roughly the names tend to be 

 arranged in order of priority with regard to dominance. 



