894 J. W. BE\YS. 



valia bonariensis and C. obtusifolia. Other typical 

 widely-scattered coast lialopliytes are Passerina rigida, 

 Asparagus sprengeri, Chiroiiia baccifera, Dispei-is 

 stenoglossa^ Acidantliera brevicollis^ Euphorbia 

 livida, Carissa grandiflora, Heliophila scandens, 

 Peucedaiium connatum^ Hyobanche sp., and the almost 

 leafless Primulaceous plant^ Saniolus porosus. As those 

 species become more abundant the taller-growing shrubs 

 among them (e. g. Osteospermum) tend to exclude the 

 herbaceous forms by shading them, and the type becomes 

 transitional to psammophilous scrub — a stage of the succession 

 which will be dealt with later. 



Though there are no stretches of beach-gravel, the belt of 

 shifting sand is interrupted here and there by rocks. In 

 such situations there is little or no change in the vegetation. 

 On the rocks at Isij)ingo the plants gathered were the follow- 

 ing : Gazania uniflora, Dimorphotheca frnticosa, 

 Passerina filiformis, Helichrysum teretif oliuui , 

 Carissa grandiflora and a species of Salicornia, all 

 of them, except perhaps the last mentioned, typical ])hTnts 

 of the sandy seashore. 



2. The Lagoor Vegetation. 



(The initial stages of the halosere, PI. XXV, fig. 1 .) 



It is not always easy to distinguish the halosere, where the 

 soil water is salt or brackish, frum the psammosere, where the 

 soil-water is not, at any rate, continuously salt. Most of 

 the sandy beach already dealt with slopes rather steeply 

 from the sand-dunes to the sea, and though the various 

 species grow often within reach of the spray, and may even 

 be submerged at exceptionally high tides, yet the sand 

 through which they gi*ow is kept moist by frequent ])re- 

 cipitation and by soakage from behind and the water is not 

 salt. At the river mouths, on the other hand, OAving to the 

 subsidence of the coast line, there are often extensive mud- 

 flats, as, for instance, in Durban Bay, where the tide ascends 



