A BED OF NETTLES. 123 



like this ? Such tricks are not uncommon in 

 bee-fertilised flowers, because they ensure the 

 pollen being- shed only when a bee thrusts his 

 head into the blossom ; but what use can this 

 device be to the wind-fertilised nettle ? I 

 think the object is somewhat after this 

 fashion. If the pollen were shed during 

 perfectly calm weather it would simply fall 

 upon the ground, without reaching the pistils 

 of neighbouring plants at all. But by having 

 the stamens thus doubled up, with elastic 

 stalks, it happens that even when ripe they 

 do not open and shed the pollen unless upon 

 the occurrence of some slight concussion. 

 This concussion is given when the stems are 

 waved about by the wind ; and then the 

 pollen is shaken out under circumstances 

 which give it the best chance of reaching the 

 pistil. 



Finally, there is the question of fruit. In 

 the fig and the mulberry the fruit is succu- 

 lent, and depends for its dispersion upon 

 birds and animals. In the nettle it takes the 

 form of a tiny seed- like flattened nut. Why 



