spatially Determined Reactions 231 



set out from a familiar region into a strange region, we fix 

 our attention on the appearance of the surroundings at 

 critical points and turnings, and on the homeward journey 

 guide ourselves by identifying these points through vision. 

 Where it can be shown that animals are influenced in their 

 homing journeys by the appearance -of the surroundings, 

 we have evidence that their vision must involve some per- 

 ception of the form and detail of objects. The fiddler 

 crab "remembers" the location of its nest, but just what 

 the memory depends upon is not clear. On one occasion 

 the observer, Pearse (568), covered the nest with his foot; 

 the female crab to which it belonged waited fifteen minutes 

 until he moved his foot, and then dashed for the nest and 

 tried to reopen it. Lubbock's (441) demonstration that ants 

 do not use visual landmarks on frequented roads will be 

 recalled (see page 97). 



In the case of bees, on the other hand, there is a good deal 

 of evidence in favor of the use of visual landmarks in hom- 

 ing. It is true that Bethe (51) was unable to note any 

 disturbance in the flight of bees back to the hive when he 

 altered the appearance of the hive, or when a large tree 

 that stood near the hive was cut down. But in this case 

 the bees had thoroughly learned the location of the hive 

 and had probably ceased to need landmarks in its immediate 

 environs. Lubbock found that bees from a hive near the 

 seashore, when taken out on the water and liberated, were 

 unable to find their way home, although the distance was 

 less than their usual range of flight on land; and he 

 ascribes their failure to the lack of visual landmarks to 

 guide them (441). Bethe, who thinks bees are guided home 

 neither by vision nor by smell, but by an unknown force 

 to which they respond reflexly, also liberated some bees 

 at sea about 1700-2000 metres from their hive, which was 



