Green Leaves at Work 



in 



FIG. 22. Four natives of South Africa. 



i, a groundsel (Senechio (Kleinia) Ha-worthii] ; 2, a typical cactus (Eichtnocactus 

 C Jormi&* 3 ' a SpUrge ( Eu Phrbia globosa); 4, a milkweed (Stafelia cacti- 



