AN ENUMEKATION OF THE BRUNIACE^ O 



preted homology to stipules is entitled to consideration. Solitary 

 or clustered crystals of calcium-oxalate occur throughout the 

 order, except in Baspalia. 



Compared with the South African flora, as a whole, the 

 Bruniaceae do not constitute an important element in the vege- 

 tation, owing to the fewness of species and their limited distri- 

 bution. What is lacking in species is often counterbalanced by 

 the number of individuals in certain cases, as instance the well- 

 nigh impenetrable thickets of Berzelia lanuginosa on Table 

 Mountain, where this species attains to a height of six to ten feet, 

 associated with the blue-flowering Psoralea aphylla and P.innnata 

 and various Eestiaceae ; it abounds near mountain-streams and in 

 swampy localities on the Cape Peninsula, Stellenbosch, and the 

 Caledon mountain ranges, and flowering from July to October, 

 when the naked, compact, subglobose, cream or sulphur-coloured 

 flower-heads form a conspicuous feature of the landscape. Mar- 

 loth, in his excellent work on the Cape Flora, depicts such a scene 

 on the edge of the Knysna Forest, near Balmoral. 



The exserted stamens and quantity of pollen of the Berzelias 

 and allied Brunias suggest that they are partially wind-pollinated, 

 but in the absence of any definite experiments this remains 

 speculative. While the majority of the species are essentially 

 xerophytic and occur on exposed rocky mountain slopes, these 

 genera are more or less confined to swamps, or at any rate to 

 places where water is present in the subsoil, and, as a consequence, 

 exhibit the greatest luxuriance of growth in the Order. Berzelia 

 lanuginosa is probably the tallest growing, while Brunia nodiflora 

 varies in height according to soil and situation ; both these species 

 are infested by Cuscuta africana Thunb., while Berzelia abrota- 

 noides, a common shrub, 2-3 ft. high, with reddish flower-heads, 

 is rarely attacked by a scale insect. Several of the Pseudoboeckeas 

 are also marsh xerophytes. 



The distribution of the Bruniaceae is essentially coastal, as a 

 reference to the accompanying table shows. They attain their 

 greatest development in the south-western region of the Cape 

 Colony, where, in the Caledon division, the group is represented 

 by approximately twenty-five species, and in the adjoining Swellen- 

 dam to the east by eighteen. As they spread eastwards (still 

 hugging the coast) a rapid diminution of species is noticeable, 

 until, in the Albany and Port Elizabeth divisions, they dwindle 

 down to one species, and reappear farther up in Pondoland and 

 Natal in Bas2Mlia trigyna. On the Cape Peninsula ten species 

 occur, and from there the diffusion of the group extends north- 

 wards, and centrally to the Oliphants Eiver and the Cederbergen 

 respectively. 



It is well known that the distribution of many plant-groups is 

 often coincident with a particular geological formation, and this 

 is strikingly illustrated in the case of the Bruniacea3, which appear 

 to be more or less confined to the Table Mountain sandstone 

 formation. Their disappearance in the vicinity of Port Elizabeth 

 is a correlative to the disappearance of the particular geological 



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