62 



PLANT LIFE. 



ordinary jungle trees kill out the mangroves, and take 



their place. 



The greatest variety and ingenuity is, however, shown 

 in the modifications of stems and branches. Generally, 

 stems are, of course, upright or vertical; and the only 

 possible way of utilising branches to spread the plant is 

 after the manner just described for the mangrove and 

 banyan. But, very often, the stem grows obliquely ; as. 



Fig. 6.— Diagrams of Non-sexual Methods of Colonisation, (i) Man- 

 grove or Banyan. (2) Suckers of Rose, etc. (3) Branches (rooting) of Goose- 

 berry. (4) Iris " rhizomes "(sympodial). (5) Walking Fern with leaf rooting. 

 (6) Bracken rhizome (indefinite growth). (7) Rooting branches of Bramble {6) 

 Runners of Strawberr3^ (9) Roots producing buds of some Rosaceae. 



for example, is the case with the Male-fern, which lies, 

 half buried, on the ground and inclined at a slight 

 anHe to its surface. In this case the buds, or young 

 branches, are given off from the parent stem m a 

 position which permits of their rooting themselves 

 without any difficulty in untouched ground. On the 



