CHAPTER XY 



THE GOLDEN RULE FOR FLOWERS 



''Get fertilized! cross-fertilized if you can, self-fer- 

 tilized if you must," that is nature's golden rule for 

 flowers. 



We have mentioned only a few of the curious and inter- 

 esting arrangements by which the pollen is in very many 

 cases prevented from coming in contact with the ovules 

 of its own blossom; but enough has been said to show 

 that this self-fertilization is generally discouraged, and 

 made in many cases either difficult or altogether impossible. 



We have now to see how cross-fertilization is provided 

 for, and by what messengers pollen is conveyed from one 

 blossom to another. These messengers are wind, insects 

 of many kinds, birds, and even in some instances that 

 most unlikely of gardeners, the ill-reputed snail. 



Plants which depend upon the wind for bringing them 

 the needful pollen have small, inconspicuous, and gen- 

 erally scentless blossoms; bright colors, sweet scents, and 

 honey, being usually confined to those plants which need 

 the services of birds and insects. The pistil-tips or stig- 

 mas of the former are also especially adapted for catching 

 and holding the grains of pollen blown upon them, for 

 they are either divided into plumes or feathers, or are 

 plentifully beset with hairs. Grasses and sedges are 

 chiefly wind-fertilized; and so, too, are many trees, such 

 as the oak, beech, hazel, birch, elm, poplar, and pine, all 



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