Plant Defences 



III 



that crown the labour of these plants declare that Nature need 

 seek no further devices for her Karroo garden. A drink of 

 water from a well driven in the Karroo shows the salty or 

 alkaline condition of the soil, and the fleshy leaves of the 

 Karroo plants remind us of the plants along the salt marshes 

 and sand dunes by the sea.^ It was once thought that roots 

 absorbed all the water required by flowering plants. The 

 water caught by the leaves of these plants suggests that they 

 also absorb moisture. Notice how the pitcher-like leaves of 



Fig. 97. — A swarm of locusts leaves little green in its path. 



Satyrium and the cups formed by the stipules and leaf bases of 

 Hydrophylax catch water. 



A swarm of locusts leaves little green in its path, and in 

 times of drought animals are not fastidious in their tastes for 

 herbage ; the juices of bitter or poisonous plants act as a 

 guard against destruction from browsing animals. 



Plants are also protected by spines or a felt of hair. Hermas 



^Plants living in dry situations are called xerophytes ; while those 

 grovv'ing by the sea or by salt pans are known as halophytes. 



