Ch. Ill, 8] FORMS OF FOLIAGE LEAVES 



69 



the stem (connate-perfoliate). Such features, for the most 

 part, seem to have a structural rather than adaptational 

 origin. 



The leaves of plants which grow in places where water 

 is scarce, or hard to absorb exhibit several features obviously 



Fig. 39. — Special forms of tip and base in leaves ; X §. Ficus religiosus. 

 with "drip" point; perfoliate Uvularia; auriculate Magnolia Fraseri; con- 

 nate-perfoliate Honeysuckle ; Caladium. 



related to reduction of transpiration. Such are, — reduction 

 in size, already mentioned ; compact or rounded forms, often 

 storing water, as in Cactus; a very thick epidermis, which 

 prevents any loss by direct evaporation ; sunken stomata with 

 an air chamber outside, or else inrolled leaves, with the stomata 



