42 WONDERS OF PLANT LIFE 



found that a lichenous growth of one type may 

 embrace several distinct species of Algae familiar 

 examples which are well known apart from this 

 strange alliance. 



A little-understood union is that to be seen 

 in the case of Beeches, Birches, and some other 

 trees. Here it is seen that the root tips are infested 

 with a network of fungus threads. It has been 

 suggested, although not actually proved, that 

 the threads act as a kind of sponge between the 

 roots and the soil, possibly taking some part in the 

 transmission of moisture. In some instances it is 

 known that the fungus threads really penetrate 

 the substance of the roots, but it does not appear 

 that any harm results. 



In the tropical forests the branches of the 

 trees offer resting-places for a host of plants. 

 These species are entirely isolated from the 

 ground, and were at one time regarded as para- 

 sitic in habit, but such is not the case. They 

 lead quite independent existences, carrying out 

 the elaboration of their chlorophyll in the ordinary 

 way. For their moisture and mineral matters 

 these perched plants rely upon rain and the atmo- 

 spheric dampness which is such a feature of the 

 steamy jungles. It is interesting to note that 

 the roots of most epiphytes are specially adapted 



