24. 



survive on the meager fertility of the substratum ajid 

 which cstn stand the hot sun and the drying of the 



winds ." Karsten (14) found ^in Polypodium imbricatum 



u 



and Po si no sum scales were present v/hich functioned 



as water absorbing organs as well as for the distribution 

 of the water drops which settle on the stem.He assumes, 

 however, that the scales are not the sole water 

 absorbers, for he found long, slightly thickened root 

 hairs which he believed to function as the main organs 

 of absorption, Wittrock (33) found no true epiphytes 

 in Sweden, He suggests that in order to assume the 

 epiphytic mode of life the plant must be ab^ to withstand 

 much shade; it must be able to form roots v/hich could 

 thrive in a thin layer of soil , ajid it must be able 

 to withstand dessication. He agrees with Schimper, Beyer 

 and the others on the characeter of the seed which 

 enables a plant to make its start as an epiphyte. 

 Went (30) made observations on epiphytes in Java and 

 found that the aerial roots of epiphytes vary in form 

 and behavior even in the same species, Some roots 

 may function only for anchor age, others for absorption 

 only and some for both anchorage and absorption, He 

 distinguishes tv/o groups of epiphytes: True epiphytes 

 and Herai epiphytes, The true epiphytes derive their 

 inorganic substances from the air or from the dust 

 accumulated on the bark; the hemiepiphytes are similar 

 to true epiphytes in their first stages of development 



