574 SCIENCE PROGRESS 



In the Annals of the Natal Museum (vol. iii. i9 l 7)> Dr. 

 Bews gives an account of the Plant Ecology of the Drakens- 

 berg Range. The soil is very poor in soluble mineral salts, 

 especially lime and phosphates, and is chiefly composed of 

 mineral matter, the organic and volatile constituents only 

 representing about 5 per cent, of the total. The veldt forma- 

 tion, which attains an altitude of over 8,000 ft., is the most 

 extensive. From the veldt of the Midlands it is distinguished 

 by the tussock habit of the dominant grasses and their more 

 xerophytic character. The Andropogon associations are 

 common, but the Anthistiria association, so frequent at lower 

 altitudes, is but poorly developed. The occurrence of veldt in 

 place of bush appears to be dependent not only on lower 

 rainfall, but also on the occurrence of frosts and exposure to 

 desiccating winds. Where the rainfall is high and there is 

 adequate protection, bush replaces veldt, so that the former 

 is particularly characteristic of south-eastern slopes. 



Maquis or fynbosch occupies the steep and unstable slopes 

 covered with loose talus. The dominant species are Cliffortia 

 spp. Myrsine africana, Passerina spp., Phytic paniculata, 

 Metalasia muricata, and a number of Compositae and Ericaceous 

 plants. This sclerophyllous vegetation is the starting-point of 

 a double succession, on the one hand through rocky fell-field to 

 tussock veldt, and on the other through rocky scrub, dominated 

 by Greyia sutherlandi, and scrub dominated by Leacosidea 

 sericea to mountain bush. This final phase is characterised by 

 Podocarpus spp., Celtis, etc. It exhibits a marginal belt 

 which, like the corresponding region of our own British wood- 

 lands, has a floristic composition very similar to the scrub. 



Marshy spots along the stream-banks and the vleis are 

 occupied by an association chiefly of Cyperaceous plants, 

 together with a number of other monocotyledons. 



On the cliffs the pioneer vegetation consists of various 

 Cyanophycese followed by Bryophytes. This cryptogamic 

 flora gives place to various types of chomophytic association 

 depending on the illumination and degree of exposure. 



C. A. Jensen has investigated the effect of decomposing 

 organic matter on the solubility of some of the inorganic 

 constituents of the soil (Jour. Agric. Research, May 191 7). 

 Filtered extracts of decomposing hay, sweet clover and barley 

 hay were prepared and utilised for the extraction of a clayey 



