some of the spikelets) are stalked, or (3) a panicle if the main 

 axis is repeatedly branched bearing racemes laterally. 



The identification of grasses is quite impossible unless 

 the dissection is proceeded with in the proper way. Very 

 little apparatus is required. A cheap mounted lens costing 

 a few shillings is necessary. It should be placed over a glass, 

 plate, on which it is convenient to have the measuring scale 

 in lines (equal to l-12th of an inch) scratched out or etched. 

 The spikelets should be dissected by means of , two mounted 

 needles (or large unmounted darning needles will serve) in a 

 drop of water, and the characters of the separate parts noted 

 as they are removed. Special care should be taken with the 

 nerves or veins in the glumes and valves. These are sometimes, 

 faint, and can only be seen when the part is immersed in a 

 drop of water. 



In the sections where the environmental or ecological 

 relationships of the grasses, and the development of (or plant, 

 succession in) the grassland types of vegetation are dealt with,, 

 certain other terms are used, and a brief introduction to this- 

 section is also necessary. The most recent work on this impor- 

 tant aspect of botanical science is a book on "Plant Succes- 

 sion" by F. E. Clements, by consulting which fuller details 

 may be learned. His system of nomenclature is adopted as. 

 far as has been found convenient. The important idea that, 

 must be grasped at the outset is that the development of th& 

 vegetation must be studied,, and it is only in so far as we 

 understand it fully that light will be thrown on many 

 extremely important economic problems. The composition of 

 grass veld, as farmers know well, is very apt to change, and it. 

 is one of the chief objects of this work to endeavour to explain, 

 at least to a certain extent, what are the underlying causes; 

 which bring about such changes. The effects of grass burning, 

 for instance, can only be properly understood if the detailed 

 plant succession in the veld has been carefully studied. 



The Formation is the final phase of a succession, or 

 climax plant community over a natural area, in which the- 

 essential climatic conditions are similar or identical. 

 Examples of plant formation in South Africa are : — (1) the- 

 Macchia of the South-Western portion of the sub-continent 

 consisting chie.fly of hard-leaved (sclerophyllous) shrubs. It 

 occurs also at higher altitudes along the Drakensberg. In it 

 a large number of drought-resisting (xerophytic) grasses are 

 present, but they occur in isolated tufts, or small patches, anJ 



