THE EPIPHYTES 149 



CHAPTER XIII 



THE EPIPHYTES 



HITHERTO we have chiefly considered the 

 relation of vegetation to an exiguous water 

 supply rather from the point of view of par- 

 simony. A short or precarious supply is 

 met by reducing the output, hoarding the 

 precious liquid, or living an abstemious life. 



But other plants have shown greater powers 

 of invention, so to speak, in overcoming 

 the difficulties of life. They have countered 

 intermittence by the construction of more or 

 less ample cisterns, and they have developed 

 new methods by which the available water is 

 absorbed. These modifications of structure 

 have rendered existence possible, and even 

 easy, in many situations from which ordinary 

 plants are debarred from establishing them- 

 selves. Perhaps the best examples of this 

 inventive resourcefulness are to be met with 

 amongst the plants that have exchanged a 

 terrestrial for an arboreal habitat. Such, 

 plants are generally called epiphytes. They 

 are in no sense necessarily parasitic, that is 

 to say they do not tax their host for food. 

 All they demand from the trees is the space 

 whereon to grow. 



