197 



air. Add to this, that they are as lungs, which sup. 

 ply the plant with the necessary quantity of a4r, and 

 as excrementary ducts, which throw off superfluities by 

 insensible perspiration. And so necessary is their ser- 

 vice, that most trees, if quite stript of their leaves, 

 will die. And if in summer you strip a vine branch 

 of its leaves, j;he grapes will never come to matu- 

 rity. Not that they are hurt by the sun ; expose them 

 to this as you please^ so the leaves remain 3 and they 

 will ripen well. 



Another point worthy our consideration is, the im. 

 mense smallness of the seeds of some plants. Some 

 are so extremely minute, as not at all to be disco- 

 vered by the naked eye. Hence the number of seeds 

 produced by some plants,, is beyond imagination. A 

 plant of red mace, for instance, and many sorts of 

 fern, produce above a million ; a convincing argu- 

 ment of the infinite understanding of the former of 

 them. 



And it is remarkable, that such mosses as grow upon 

 Avails, the roofs of houses and other high places, have 

 seeds so excessively small, that when shaken out of 

 their vessels they appear like smoke or vapour. Those 

 therefore may either ascend of themselves, or by an 

 easy impulse of the wind be raised to the tops of 

 walls, houses, or rocks. And we need not wonder 

 how the mosses got thither, or imagine they sprung 

 up spontaneously. 



Concerning vegetables in general we may farther 

 remark, 1. That because they are intended to be 

 food for numberless species of animals, therefore na- 

 ture has taken so extraordinary cire, and made so 

 abundant provision, for their propagation and increase. 

 So that they are propagated and multiplied, not only 

 by the seed, but also by the root ; producing shoots 

 or off-sets in some, creeping under ground in others. 

 Some likewise are propagated by slips or cuttings ; 



