130 WONDERS OF PLANT LIFE 



the leaf-stalk that nearly all extensions of the 

 plant arise. Not a few plants are able to produce 

 fresh specimens on their foliage, whilst of course 

 many of the low forms of vegetable life increase 

 in no other way than by a system of leaf extension. 

 We shall not be far wrong in regarding the leaf 

 as the most important organ of the plant. 



In considering the foregoing instances the 

 student can scarcely fail to have been struck with 

 the importance of those examples which are in 

 some way departures from the normal. Cer- 

 tainly it seems that, as the great scheme of evolu- 

 tion goes forward, the traces of the origin of things 

 become less and less distinct. It will well repay 

 anyone who is interested in the subject to keep 

 a sharp look out for freak flowers ; for, as we 

 have seen, it is most likely that in these forms 

 we shall find enlightenment as to the beginnings 

 of the floral organs. The observer will find a 

 much more fruitful ground for observation in 

 the garden or greenhouse than out in the country. 

 It is a well-established fact that under cultivation 

 both animals and plants are much more prone 

 to vary than when they are in a state of nature. 

 We are not very clear as to the reason for this 

 tendency, but the fact is beyond dispute. One 

 of the most remarkable cases which has arisen 



