THE SUMMER DROUGHT. 175 



You might suppose that two different plants were 

 joined. Kerner's explanation seems to be as follows. 

 The leaves of the rosette are more permanent, and 

 have to go through the Summer drought, whereas 

 those on the upright stem will disappear as the fruit 

 ripens. 



Of the individual hairs which compose those 

 sun-shields I have not room to write. But the 

 epidermal appendages of the Riviera plants are well 

 worth study. The branched hairs of the disagreeable 

 and dangerous Plane tree (Platanus) are figured in 

 Botanical books; as also are the globular glands 

 which hold the perfume of the Lavender, perched each 

 upon a little stalk, and sheltered under spreading 

 hairs. The spangles of the sacred Storax, and the 

 lancet-shaped sting of the beautiful Wigandia, may 

 be taken as other instances and types. 



I have explained two different methods of com- 

 bating the drought. A third consists in hanging the 

 leaf-blades edgewise to the sky, so as to present the 

 smallest possible surface to the sun. The (later) 

 leaves, of Eucalyptus (Fig. 30) are an instance of this 

 arrangement. 



Again, it is possible that by rolling in the margins 

 of the leaf a plant may gain an advantage in the 

 scorching Summer days, for it will thus diminish the 

 area exposed to the sun's rays, and also lessen evapo- 

 ration by hiding some of the stomata. Familiar 

 examples are the pretty pair of wall-weeds, Phagnalon 

 (or Conyzd), and the still prettier Everlasting 

 (Helichrysuiri). Rosmary, Erica, and Coris may be 

 added. 



Yet another plan is adopted by Nerium Oleander, 



