106 



PLANT STUDIES 



that of the banyan tree, whose wide-spreading branches 

 are supported by prop roots, which are sometimes very 

 numerous (see Fig. 101). The immense banyans usually 



illustrated are 

 especially culti- 

 vated as sacred 

 trees, the prop 

 roots being as- 

 sisted in pene- 

 trating the soil. 

 There is record 

 of such a tree in 

 Ceylon with 350 

 large and 3,000 

 small prop roots, 

 able to cover a 

 village of 100 

 huts. 



69. Parasites. 

 — Besides the 

 roots mentioned 

 above, certain 

 plants develop 

 root-like pro- 

 cesses which re- 

 late them to hosts. 

 A host is a liv- 

 ing plant or 

 animal upon 

 which some 

 other plant or 

 animal is living 

 as a parasite. 

 The parasite gets its supj^lies from the host, and must be 

 related to it properly. If the parasite grows upon the 

 surface of its host, it must penetrate the body to obtain 



Fig. 102. A dodder plant parasitic on a willow twig. The 

 leafless dodder twines about the willow, and sends out 

 sucking processes which penetrate and absorb.— After 

 Strasburger. 



