Geographical IJoia.nv. -55 



of the vegetation of South Africa. In the 47 pages which he 

 devotes to the Kalihari and the Cape regions, he discusses the 

 topography of the countn, the climatic conditions, the (iistribution 

 of a number of orders and genera, the various forms of plant lite, 

 e.g., succulents, heath-formation, grassy plains, forests, etc., the 

 origin of some of the larger systematic groujDS, the connections with 

 other floras, and many other points. If one considers that he had to 

 treat in this way the vegetation of the whole globe, and that he had 

 not visited South Africa, but had to depend entirely upon the writ- 

 ings of others, one cannot but admire the genius who i)erf()rmed 

 this task. 



A different arrangement was adopted by Rehmann, who. having 

 travelled in South Africa, and made large collections of plants, pub- 

 lished his results in 1880 at Krakow. 



One of the errors into which (iri.seljach was led is the view that 

 the Orange River forms a natural boundary lietween the Kalihari 

 and the Cape floras. That error was rectitied by Dr. H. Holus in a 

 contribution to the Journal of the Linnean Society (vol. j 4, p. 482), 

 and more fullv later on in his " Sketch of the Flora of South Africa " 

 (1886). In this treatise, which is modestly called a sketch, the 

 floral regions of South Africa are arranged more in accordance with 

 Drege's original divisions and subsequent observations. Jt is shown 

 that the so-called Cape flora of Grisebach consists of two. or perhaps 

 three, quite distinct regions, and that the Orange River flows through 

 the southern extension of the Kalihari vegetation, the portion which 

 lies to the south of the river being known as Kushmanland. .Special 

 stress is laid upon the great difference which exists between the 

 South Western corner of the Cape and the other portions of the 

 country, the typical Cape flora being confined to the narrow sickle- 

 shaped strip between the coast and the mountain ranges which form 

 the Western and Southern boundaries of the Karroo, viz.. the Cedar- 

 bergen and the Zwartebergen. 



The country to the north of the Zwarteliergen is (Jivided into 

 two regions, viz.. the Karroo and the composite region, the latter 

 comprising the Xieuwveldt and the high plains to the north of 

 Beaufort West. 



A somewhat dift'erent view of the relation of our various regions 

 to each other is adopted by Engler in his "'Versuch einer 

 Entwicklungsgeschichte der Pflanzenwelt.' Part II., which' appeared 

 a feAv years before Dr. Bolus' sketch, viz.. in 1882. Engler' adopts 

 the South We.stern region of Bolus, and calls it the Cape flora, but 

 all the others, inclusive of the Karroo, he finds so closely related to 

 the large tropical and sub-tropical area of Central Africa, that he 

 considers the Karroo simply as " the last outlayer and the poorest 

 tiranch of this vast region." Some modifications of these various 

 views are adopted bv two other works on general geogra[)hical botanv, 

 viz., by Drude in his " Handbu<:h der Pflanzengeographie "" (1890), 

 and by Warming in his " Oekologische Pflanzengeographie "' (1896). 

 I^rude combines Rehmanns and Bolus" plans, and goes even a step 

 further by sub-dividing the latter's South Western region into two 



