Io6 Plants and their Ways in South Africa 



protecting its stomata. The cells bordering the stomata over- 

 arch, forming a little hut with an opening at the top (Fig. 89), 

 so small that the vapour can pass 

 out but a drop of rain will not run 



t=4-JlJL=^ ■■.7^\y\^ \ The heaths have small needle- 



shaped leaves ; their edges are rolled 

 back so as to form partially enclosed 

 channels on the under side where 

 the stomata are placed. These 

 channels are protected by a lining 

 of hairs, making sometimes a close 

 white mat. Many plants have 

 between which the stomata are placed, 



Fig. 89. — Section of sugar-bush 

 leaf through a stoma : a, the 

 guard-cell; b, projecting dome; 

 c, thick cuticle. 



strongly ribbed stems 



so that transpiration is lessened. 



Fig. 90. — Crassula pyraniidalis , L. 



Our finest heaths are found in the Caledon and Riversdale 



