58 



high, and does not flower so freely, though it flowers earlier. 

 On the whole it should be ranked as a luoderately mesophvtic 

 type. It is a yery good grazing grass, but it yaries somewhat 

 in this respect also. The glaucous "Blue grass" yariety is 

 considered more yahuible than the tyjjical Eed grass. Fig. 5 

 shows a transyerse section of a rather narrow leaf of AntJiis- 

 tiria. It is yery similar to the Audropogons. There is a yery 

 distinct midrib, which enables the leaf to fold (conduplicate) 

 in dry weather. The ridges are nearly obsolete, and between 

 them are large epidermal water storage cells which do not 

 function as motor cells. The leaf therefore does not roll ujj 

 from the margins. The main yascular strands are girdered by 

 sclereuchyma aboye and below, but the total amount of fibre 

 is not escessiye. 



Fio- 



-Transverse Section of a portion of a leaf of Anthistiria imberbis 

 (x about 60). 



.\nlho\anlhnni. Two species A. dregeanmn and A. 

 tango are South Western, and the third A. ecldonii is a Moun- 

 tain Yeld species of the Transitional belt and Eastern side. 

 It grows in isolated tufts or tussocks. Like the European 

 A. odoratum this grass is sweet scented. 



Arlslida. (See Fig. 1 F.) The most important genus in 

 the early stages of succession, throughout South African grass- 

 land, and dominant oyer enormous areas of open or semi-open 

 grassland or semi-desert of the Western side. As Stapf has 

 pointed out the genus Aristida contains two ecological types, 

 one a desert type, recruited chiefly from the section Stipa- 

 grostis, which has 3 neryed glumes and plumose awn bristles, 

 and the other a steppe type fcom the sections Chaetaria and 

 Arthratherum, which haye 1 neryed glumes and glabrous 

 awns, but the two types merge into one another. 



