SEED -SCATTERING 



that the dying of the walls of the dry fruit lets 

 strained parts straighten out. The pulling of the 

 trigger is often due to the state of the weather. 



Another simple kind of scattering is seen in a few 

 dry fruits which fix themselves readily to passing 

 animals, such as rabbits, and eventually fall off, it 

 may be far from the site of the parent plant. The 

 little brown nutlets of jack-run-the-hedge or 

 cleavers are covered with roughnesses which take a 

 firm hold ; those of the burdock have long crochet- 

 needle-like hooks ; and the awns of grasses also fix 

 on very readily and firmly. 



Water-birds often carry seeds of water plants from 

 pool to pool on the mud attached to their toes, and 

 there are often seeds inside the clodlets which land- 

 birds get fixed on to their damp feet. Darwin made 

 a thorough study, after his wont, of the fauna and 

 flora of birds' feet, collecting the clodlets and 

 moistening them, to see what would come forth. 

 He proved up to the hilt the importance of this mode 

 of transport, and he was rewarded on one occasion 

 by obtaining from one bird no fewer than eighty 

 germinating seeds. 



A third kind of scattering is by means of para- 

 chutes, which make it easier for the fruits to be 

 carried by the wind. We see the thistle-down and 

 dandelion-down with their beautiful hairy para- 

 chutes " sailing before the wind." It is interesting 

 to watch one enter by the open window of a railway 

 carriage, sail around once or twice, touching the 

 cushions for a moment, and then move on again, 

 finally passing out where it came in. There is 



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