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THE ACACIAS OF SOUTHERN AFRICA. 

 By R. Maeloth, Ph.D., M.A. 



[Read 26th October, 1887. J 



'There is scarcely any book on travel in Southern Africa that does 

 not contain some pages dedicated to the description of thorns and 

 spines on plants. Although most of our travellers took very little 

 interest in botany, they could hardly help paying considerable atten- 

 tion to a subject that was forcibly obtruded upon them every day. 

 In the coast districts of the Cape Colony and in the regions extending 

 towards the north-east spiny bushes or trees take a less prominent 

 place in the vegetation of the country, and those armed with such 

 weapons belong to several very different families. In the central 

 regions however and especially in those vast tracts which extend 

 north of the Orange River far beyond the tropic of Capricorn, one 

 family, or to speak more properly one genus, of thorny trees comes 

 to the front and impresses its character on the landscape. This is 

 the genus Acacia. Two species of acacias are familiar to all of us, 

 namely the common Karroo- thorn and the so-called Port Jackson 

 willow. The latter is not indigenous to this country, but comes from 

 Australia, and I may here mention, that the large genus acacia, which 

 contains over 400 species, is distributed over three continents : 

 Australia, Africa and America. On our continent it is principally 

 found in the northern and southern countries ; but our number of 

 species is much inferior to that of Australia. The Port Jackson 

 willow being a typical representative of the bulk of the Australian 

 -acacias, and the Karroo-thorn one of ours, the difference between 

 the two branches of the genus is apparent. 



There are nineteen species known from South Africa, six of which 

 belong to the eastern coast districts, namely : A, arabica, natalitia, 

 raffra, spitioza, Kraussiana, peimata, whilst three have been found 

 only in the eastern Transvaal : A. ferax, Burkei and eriadenia. One 

 species only, the above-mentioned Karroo-thorn, reaches our neigh- 

 bourhood, the remaining nine species being restricted to the Kalahari 

 region, where I collected them all but one. To these must be added 

 seven new species which I discovered in Damaraland, namely : A, 

 .hereroensis, Engler ; A. trispinosa, Marloth et Engler ; A» dulcis, 



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