174 The Great World's Farm 



world, which they cannot do without offspring, it is better 

 for them to have some seed, even poor seed, rather than 

 none at all. And to insure this some plants manage to 

 bear seed of both sorts; some fertilized by the pollen of 

 its own blossom, some, if possible, by that brought from 

 outside, so that if by any chance the latter should fail, 

 they may stiU have something to fall back upon. 



There is, for instance, that ubiquitous little plant, the 

 common chickweed, weak-stemmed and fragile-looking, 

 but not in the smallest danger of dying out, for it goes on 

 sowing itself through many m.onths of the year. Its first 

 crop of seed is fertilized quite early in the spring, so early 

 that the plant is left to itself, and has to make the best of 

 its own pollen, which it does in the most thrifty way pos- 

 sible. The pollen is never scattered, so there is no waste, 

 but while still in the anther-sacs, it sends out tubes in the 

 direction of the pistil-tip, which it reaches without fail. 

 This process takes place while the flowers are still only 

 buds, so that pollen and tubes are carefully protected. 

 The seed thus produced may be poor, much of it may 

 even be useless, but at least what there is, is better than 

 none; and later in the season, if circumstances are favor- 

 able, better seed will be produced by pollen brought from 

 other plants. 



Generally speaking, pollen-grains do not begin to swell 

 until they actually touch the moist tip of the pistil, but in 

 these early blossoms of the chickweed and some other 

 plants, they never leave the anthers. The sweet violet, 

 in like manner, bears some buds, smaller than the rest, 

 which never open. These produce but a few grains of 

 pollen, as there is no waste to be allowed for, and they 

 send out long tubes without leaving the anthers^ 



