Sensory Discrimination: The Chemical Sense 105 



tion of bees visiting flowers with intact corollas to those 

 visiting flowers with the corollas removed was 66 : 18 

 (778). Kienitz-Gerloff criticises Plateau's figures and the 

 accuracy of his experiments (400). Forel found that a 

 bee with the antennae and all the mouth parts removed, 

 hence probably incapable of smell, returned to flowers 

 for honey, though of course without success (231). An- 

 dreae thinks that among diurnal insects those which live 

 on the ground, and take but short flights, are more influ- 

 enced by smell ; while the freely flying insects are attracted 

 by the sight of flowers (5). On the whole, inconspicuous 

 flowers are more often f ertilized by wind than by the visits 

 of insects. 



28. How Bees Find the Hive 



Most complicated of all is the problem as to how bees find 

 their way back to the hive. It is obvious that the simple 

 ant method of following a chemical trail is ruled out for in- 

 sects that fly. Bethe abandons the puzzle as insoluble (51). 

 Von Buttel-Reepen attempts at length, and with a vast 

 amount of apic lore, to refute his position. It would be im- 

 possible to give more than the briefest statement of the 

 arguments of both sides. Bethe maintains that the smell 

 of the hive does not guide the bees back to it, because he 

 found that if the hive were rotated slowly enough to allow 

 the cloud of nest smell at the opening to move with the 

 opening, the bees returning would not follow it for more 

 than 45, but would go to the place where the opening 

 had been. He thinks they are not guided by sight, be- 

 cause when he completely changed the appearance of the 

 hive, masking it with branches and other coverings, the 

 bees were not disconcerted, but flew straight to the mouth 

 of the hive. He brings other evidence against the vision 



