INTELLIGENCE IN INSECTS 199 
distance and a black piece of paper with a hole in the center 
was placed over the nest so that the hole in the paper lay 
directly over the opening of the nest. The bee returned and 
entered her nest after hovering for but a few seconds over the 
black paper. Finally all the accessories were swept away 
and the region around the nest covered uniformly with 
green grass leaving the opening uncovered. On her return 
the bee was disconcerted, circled about the nest for about 
two minutes and finally entered it. 
The hole of another species of burrowing bees was found 
near one of a series of bricks which formed the border of a 
walk. Near the hole was the cover of a bottle. During the 
absence of the bee Turner punched holes of the same diameter 
as the bee’s nest and bearing the same relation to the other 
bricks as the nest did to the brick near it. The top of the 
bottle was placed near one of these artificial holes. On her 
return the bee alighted some distance away and came along 
the series of bricks until she encountered the hole near the 
bottle cover when she immediately plunged into it. She 
quickly recognized her error, withdrew, and soon found her 
own hole. During her second absence holes were punched 
in front of several more bricks on either side of the nest, but 
the bee on her return once more entered the hole near the 
bottle cover. She emerged, hovered over the spot, and 
again entered the same hole, but soon came out and found 
her own nest. Evidently the bottle cap served as a land- 
mark indicating the position of her nest. The environment 
of the different holes was so similar that a change in the 
position of this one object changed the principal feature of 
the local topography. 
There is no support here for Bethe’s theory of a mysteri- 
ous force, the assumption of a dead reckoning process, or 
the “kinesthetic reflex” of Pieron. The results are only 
