The Golden Rule for Flowers 183 



begun to penetrate downwards through the style. In 

 these cases the ovary seems to be excited to growth by 

 the pollen, though not in the usual way, and before the 

 ovules are affected. 



But in many plants the ovary, and even ovules, may be 

 fully developed, altogether without pollen; though in this 

 case the ovules do not become seeds any more than the 

 ** stones" of the Martinique date becomes seeds, and no 

 plant can be raised from them. 



Among the plants which ripen the ovary without the 

 help of pollen are the Zante "currant" (really a small 

 grape), many Maltese oranges, and some kinds of apple. 



While some ovules are so independent as to be able to 

 grow to the size of seeds, and even to assume the appear- 

 ance of seeds, without being fertihzed, there are, on the 

 other hand, some — as, for instance, those of the orchids — 

 which are not even formed until the pollen-tubes begin to 

 grow towards the place where they should be. The pollen 

 in these cases not only fertihzes them, but though still at 

 a distance is the means of bringing them into being. 



Of course, as pollen is so light, and easily blown about, 

 many plants may at times be fertilized by the wind, besides 

 those which are especially dependent upon it. Not many, 

 one would suppose, are fertilized by water; yet there are 

 one or two instances of this too curious to be passed over. 



One of these is that of a small water-plant, nearly re- 

 lated to the duckweeds, which bears two blossoms inclosed 

 together in a boat-shaped sheath, which floats upon the 

 water. In the upper part of the sheath is a perfect pistil, 

 with its ovary, short stalk, and stigma; in the lower part 

 are the anthers containing pollen, which cannot by any 

 possibility reach the stigma unless rain happens to fall 



