178 
Beekeeping 
secreting plants. That bees differentiate between flowers 
which are encountered in their flights is shown by the fact 
that they usually visit but one species on a trip (p. 119). 
Finding of the hive. 
It is well known that bees normally return to the right 
hive. The fact that strange bees are not usually admitted 
may be explained on the basis of difference in colony odors 
but this does not explain the method by which they find 
the right hive in the majority of cases. Bethe 1 asserts that 
the bees are led back to the hive by an “unknown force” 
but, as v. Buttel-Reepen points out in his discussion of 
memory of place in bees, this explanation is not satisfactory, 
and cannot be accepted until the known forces are eliminated. 
It will be recalled (p. 105) that young bees take “play flights” 
on warm days. If bees which have not taken such flights 
are taken out a few feet from the hive, they fail to return. 
Bees that have had some experience on the wing are able to 
return from short distances, and, finally, old bees are often 
able to return if taken away two miles or more. They 
evidently increase in efficiency with experience. It is also 
known that if the hive is moved a foot or more in any direc¬ 
tion the returning bees seek the entrance to the hive in the 
old place. If the hive has been moved only a short distance 
they may soon find it by searching, but if it is moved several 
feet they may fail to find it. 
If bees were attracted to the hive by odor, the field bees 
would probably have no difficulty in finding it if it were 
moved perhaps a mile. Under such circumstances a short 
distance would make no appreciable difference and yet the 
moving of the hive a foot often delays their entering it. Odor 
is therefore evidently not the guiding sense. 
Bees in the field cannot always see their hive, and in all 
probability, they can see neither far nor distinctly. If 
1 Bethe, A., 1898. Dllrfen wir Ameisen und Bienen Psychisehe Quali- 
tiiten zuschreiben ? Arch. f. d. ges. Phys., LXX, also as separate, 1898. 
Bonn: Emil Strauss, with different paging. 
