Spatially Determined Reaction 235 



lost track of it. She approached it several times, but there 

 are no landmarks on the B. field. After five minutes our 

 wasp flew back to look at her spider," which she had dropped 

 about three feet away, "and then returned to her search. 

 She now began to run into the B. holes, but soon came 

 out again, even when not chased out by the proprietor. 

 Suddenly it seemed to strike her that this was going to 

 be a prolonged affair, and that her treasure was exposed 

 to danger, and hurrying back she dragged it into the grass 

 at the edge of the field, where it was hidden. Again she 

 resumed the hunt, flying wildly now all over the field, 

 running into wrong holes and even kicking out earth as 

 though she thought of appropriating them, but soon pass- 

 ing on. Once more she became anxious about the spider, 

 and, carrying it up on to a plant, suspended it there. Now 

 she seemed determined to take possession of every hole 

 that she went into, digging quite persistently in each, 

 but then giving it up. One in particular that was close by 

 the spider seemed to attract her, and she worked at it so 

 long that we thought she had adopted it, for it seemed to 

 be unoccupied. At last, however, she made up her mind 

 that all further search was hopeless, and that she had 

 better begin de novo; and forty minutes from the time that 

 we saw her first she started a new nest close to the spider, as 

 though she would run no more risks" (572). An occur- 

 rence of this kind certainly lends color to the ' recognition 

 of landmarks' theory. On the other hand, the Bembex 

 wasps themselves find their nests with unerring accuracy, 

 though there is no landmark in the field. Fabre noted 

 that Bembex wasps could not be led astray by any modi- 

 fication of either the look or the smell of their nests, and 

 thought a peculiar form of space memory, unparalleled 

 in our own experience, must be involved in the nest-find- 



