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Transactions of the Royal Society of South Africa. 
5. The northern, shaded slopes of the valleys showed a conspicuously 
different plant population from the southern exposed slopes during the 
winter months. In the summer months the contrast was not as sharply 
marked. This is attributed largely to the fact that in winter the sun 
shines on the northern slopes for a short period only of the day, while the 
southern slopes get most of the available sunlight. 
6. During 1920 the shrubs were divided into two classes : (a) those 
where the underground parts had survived the fire and from which new 
shoots arose, and (b) those which were killed by the fire and which repro- 
duced themselves hv seed. The Rhenoster bush falls in class (b), and is 
clearly favoured by burning. 
7. The removal of the vegetation by the fire helped the process of soil 
erosion. This process was also aided by man and cattle. Several small 
washaways occurred on the area subsequent to the fire. 
8. The area is shown to be deficient in several typical south-western 
families, but to what extent this may be attributed to the influence of 
repeated fires is not clear, and the view is brought forward that soil may be 
the determining factor in this case. 
LITERATURE CITED. 
(1) Hall, Sir A. D. — The Soil, third edition, 1920. 
(2) Harvey, W. H.— Memoirs of Dr. Harvey, 1869. 
(3) Marloth, R. — Das Kapland, Jena, 1908. 
(4) Palladin, W. — Plant Physiology, edited by B. E. Livingston, 1918. 
(5) Phillips, E. P. — " A Preliminary Report on the Veld-burning Experiments at Groen- 
kloof, Pretoria," South African Journal of Science, xvi, 1920. 
(6) Phillips, E. P. — " Veld-burning Experiments at Groenkloof," Union of South 
Africa, Department of Agriculture, Science Bulletin, No. 17. 
