CHAPTER V. 



DEFENCE. 



Although, as described in the previous chapter, there 

 are many dangers in the seedhng stage of existence, 

 plants continue to require protection during their whole 

 hfe, and must be prepared for all sorts of emergencies. 



Rain, hail, wind, snow, sunshine, and especially 

 drought are very dangerous, and have to be provided 

 against. The competition with other plants for water, 

 soil, and sunshine, is excessively severe. There are 

 too, whole series of animal and other enemies. In fact, 

 the entire animal world lives, either directly or indirectly, 

 upon vegetation. Every species of plant therefore must 

 protect itself from browsing animals and injurious insects. 

 There are also vegetable fiends such as the Mildews, 

 the Rust fungi, and Germs which beset the developing 

 plant at every stage of its life, and at every part of 

 its body, and against whose attacks it must provide. 



A list of the enemies of any one particular plant, 

 say the Apple, will give a more distinct idea of these 

 dangers to which plants are exposed, and of the 

 thoroughgoing modifications which these have brought 

 about in vegetable structure. First, as regards the 

 stem, there is under the bark and next the wood a 

 delicate layer of living and growing tissue known as 

 " canibiiimr This canibiuui is the favourite food of 

 certain beetles which make their burrows within it. 



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