83 



Bechuaualand, also in the Free State and Transvaal. It is 

 xerophytic, with convolute leaves, and numerous villous, 

 conical, innovation buds at the base. Hence it is more or less 

 bulbous. Hackel distinguishes other species, viz., S. quinque- 

 seta and S. pappophoroides, from various places in the Kala- 

 hari, Namaqualand, Hereroland and Amboland. 



Scleropoa rigida ( = Poa rigida L.), an annual ruderal 

 species introduced at the Cape. 



Secalc africanum. Collected by Thunberg on the Rogge- 



«/ D Do 



veld, which, he says, were named after this rye grass. 



Setaria. (See Fig. 2 D.) The two species S. sulcata and 

 S. lindenhergiana of the section Ptychophyllum are very 

 distinct from the others. They have broad leaves which are 

 plicately folded when young. The former is the more abun- 



Fig. 18. — Transverse Section of a portion of a leaf of Setaria nigrirostis 



(x about 70). 



dant, being usually found round the margins of Forest. 

 S. perennis is a Yeld species, S. verticillata a widely distri- 

 buted weed, and the rest are Vlei species. S. aurea often 

 forms definite consocies in the hydrosere. With the exception 

 of S. appendiculata , which is Western only, the Setarias are 

 Eastern in their distribution, being closely allied to the 

 Panicums. Fig. 18 shows the appearance of a leaf of S. 

 nigrirostis in cross section. The ridges are not pronounced, 

 and the bundles are not girdered, there being only small 

 patches of sclerenchyma above and below the main ones. 

 There were usually three smaller bundles between the larger. 

 The midrib is distinct, but the large cells in the shallow 

 grooves function as water storage cells and not as motor cells. 

 The leaf remains flat. 



Spartina slricta. A European strand and salt marsh 

 plant, only found in South Africa along the seashore at Port 

 Elizabeth. 



