144 THE ROMANCE OP SEED-SOWING. 



Besides these four chief methods of dispersion, there is one 

 other occurring in a few cases and deserving of notice. I refer to 

 movemefits of the plafit itself — i.e., of some portion of it. 



Dandelion, after lying horizontally among the grass while 

 ripening its seed, rises to an erect posture, thus enabling the wind 

 to act on the parachute-like pappus surmounting the fruit. On 

 the other hand, many plants, by their movements, provide not for 

 dispersion of seeds by wind, but for burial of them in the soil. 

 The small white Subterranean Clover [Trifolium subterraneii?n) of 

 our commons and downs is a good example. Here, instead of 

 the large number of florets seen in a head of purple Clover 

 and others, only about three of the bunch become well-developed 

 florets with pods ; the rest remain abortive in a sense — />., they 

 are developed into a number of short fibres, each having four 

 or five divisions like the fingers of a hand, but of course very 

 minute. 



These palmate fibres together form a small green knob in the 

 centre of the flower-head. The whole plant lies close to the 

 ground, except that at blossoming-time the three florets stand 

 erect to secure fertilization by the Bees. This accomplished, the 

 stem lengthens and turns downwards, the palmate fibres are deve- 

 loped, and, being central, on touching the earth they bury them- 

 selves with a screwing sort of movement, thus working a hole, 

 into which the three pods (which have by this time bent 

 downwards) are drawn and effectually buried. Thus the plant 

 safely stores away its pods, full of seeds, which ripen under- 

 ground during Autumn and grow up in Spring. The plant, 

 growing only on ground quite closely cropped by animals, in this 

 way secures reproduction by burying the pods safely out of harm's 

 way. It sacrifices some of its flowers in order to make natural 

 gimlets, which can dig a grave for the three seed-bearing ones ! 



Many other plants, possessing the usual aerial pods, have also 

 some subterranean ones, usually shorter and with fewer seeds, the 

 smaller number being an advantage, as they the more easily 

 flourish when trying to germinate close to one another, while in 

 the aerial pods a larger number of seeds evidently secures a better 

 chance in the scattering process. Of these plants we find 

 examples in some species of Vetch, Vetchling, and Cress. In 



