INTRODUCTORY. 13 



fruits, like the strawberry or the orange ; and in 

 all these instances, though the fruit or outer coat 

 is edible, the actual seed itself is hard and indi- 

 gestible, like the orange -pip, or is covered with a 

 solid envelope like the cherry-stone. Numerous 

 other examples we shall see by and by in their 

 proper place. For the present, we have only to 

 remember that plants to some extent provide 

 beforehand for their children, and in many cases 

 take care to set them out in life to the best 

 possible advantage. 



Most of these points to which I am here 

 briefly calling your attention are true only of 

 the higher plants, and especially of land-plants. 

 For we must not forget that plants, like animals, 

 differ immensely from one another in dignity, 

 rank, and relative development. There are 

 higher and lower orders. We shall have to 

 consider, therefore, their grades and classes 

 to find out why some are big, some small ; some 

 annual, some perennial ; why some are rooted in 

 dry land, while some float freely about in water ; 

 why some have soft stems like spinach and 

 celery, while others have hard trunks like the 

 oak and the chestnut. We shall also have to 

 ask ourselves what were the causes which made 

 them differ at first from one another, and to 

 what agencies they owe the various steps in 

 their upward development. In short, we must 

 not rest content with merely saying that the 

 rose is like this and the cabbage like that ; we 

 must try to find out what gave to each of them 

 its main distinctive features. We must " con- 

 sider the lilies, how they grow," and must seek 



