PLANTS ON THE MOVE 195 



the glossiest feather would scarcely be proof, if 

 it touched it at just the right condition of 

 atmosphere, and it is a fruit that by its tininess 

 and lightness would not call upon the bird about 

 to migrate for an immediate preening. Prunella 

 has probably done the journey from England to 

 South Africa many times. 



The seeds of Lyihrum and many other waterside 

 plants fall into the water and make a film that 

 closes at once on any solid body that meets them. 

 Not in themselves sticky, they are highly so by 

 the suction that a damping gives to such light 

 particles, and as waterfowl and waders are among 

 the most active of our migrants, the purple 

 loosestrife must, like the prunella, owe much to 

 the birds for its extraordinary distribution. When 

 no water bird touches them, the autumn floods 

 take them and wash them out on some meadow 

 bank many miles from home. 



It is hard to find any plant that has not some 

 visible means of migration. It is as imperative 

 for plants as for animals to care for their progeny, 

 and there is no more necessary care than the 

 provision of new soil wherein to grow. An obvious 

 method differing from all the others just named is 

 the surrounding of the precious seed with a fleshy 

 fruit bribing the birds to their duty, just as the 

 honey bribed the insects to carry the pollen. 



It is strange that man has made so much of 

 fruit, that is of the fleshy surroundings of fruit, as 

 an article of diet. It is of the essence of the 



