A SPOTTED ORCHIS. 



pollen ; the use they make of birds as 

 dispersers of seeds ; the use they make 

 of natural agencies, such as wind or stream, 

 to waft winged thistle-down, to carry the 

 parachutes of the dandelion and the willow, 

 or to float the male blossoms of such water- 

 weeds as vallisneria. Behold ! I show you 

 a mystery. The secret of the whole thing 

 is that plants, being fixed themselves, must 

 needs employ birds and insects as their 

 Pickford vans must rely on wind or stream 

 for such casual services as wind or stream 

 can easily afford them. Only in a few 

 species can they effect anything like active 

 movement for themselves, as one sees in 

 the rooting runners of strawberries, or the 

 wandering tubers of certain vagrant orchids, 

 which spread far afield from last season's 

 nesting-place. These are clever devices for 

 securing fresh virgin soil " rotation of 

 crops," as the farmers put it. 



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