ON THE FLORA OF THE GREAT KARASBERG 1 
I. INTRODUCTION 
By H. H. W. PEARSON 
The pages immediately following will be occupied by a list of the 
flowering plants and ferns collected on the Great Karasberg by the Percy 
Sladen Memorial Expedition in the early summer of 1912-13. 
This flora is of particular interest on account of the form and geographical 
position of the range on which it occurs. A detailed discussion of the 
phyto-geographical results of the expedition will be postponed until the 
determination of the collections has been completed. A few introductory 
remarks on the general features of the Karasberg, its position and climate, 
and on the localities named in the following list, may serve a useful purpose 
at this stage. 
A traveller landing at any point on the South-west African coast and 
proceeding inland, rises gradually to a more or less rugged and broken 
mountain-belt beyond which he emerges upon the Central African plateau 
between 3000 and 4000 feet above the sea. This mountain-belt, representing 
the eroded edge of the central plateau, in different parts of its length, lies at 
distances from the coast varying from 10 to about 100 miles. 
The coastal zone which separates this line of mountains from the sea 
enjoys a very low rainfall ; throughout the greater part of its length it 
is a desert of a very pronounced type. Its flora includes a number of 
endemic genera as, e.g. Welwitschia and Acanthosicyos ; for the most part, 
however, it consists of forms more or less closely related to those of 
various parts of the central plateau — the Karoo, the Upper Region and 
the Western Kalahari. With these are almost certainly a number of species 
descended from forms whose affinities are found in the north rather than 
in the east. A small element of this desert flora will probably be found 
1 Percy Sladen Memorial Expeditions in South-West Africa, Report No. 69. Assisted 
by grants from the Eoyal Society and the South African Government. 
A. E. H. }. 
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