62 THE LEAF 



nature and position of the protective organs and decide as to their special 

 purpose, whether as defenses against heat, cold, dust, or insects and 

 other animals. Examine the tendrils of various climbing plants and tell 

 from their position whether they represent stipules, leaves, or branches. 

 Look for instances of transformed leaves of any kind and try to under- 

 stand the nature and object of the transformation. Always be on the 

 alert for transformations and disguises everywhere, and account for 

 them as far as you can. 



