MEMORY OF PLACE IN BEES. 



In general, we should not set up a new unknown 

 force to explain natural phenomena until it has been 

 proven that they can not be explained by the known 

 forces.— Aug. Weismann, p. 539. 



According to Bethe, bees are "led back to the hive by a force entirely unknown to us. 

 This force does not adhere to the hive itself, and it does not lead bees back to the hive 

 itself, but to the place in space which the hive usually occupies. It does not act at 

 boundless distances. It is an old experience of bee-keepers that they can take a colony 

 to another stand without fearing that the bees will return to the old place, if the new 

 spot is only more than six kilometers from the old. It follows, then, that this force acts 

 at most at a distance of six kilometers, since the impulse to return to the hive is the 

 strongest of all impulses in bees. But' I\ believe that the zone of action of the force is 

 not a circle with a radius of six kilometers, but of only between three and four kilometers. 

 If the circle had had a radius of six kilc meters, then the bees of the transported hive 

 would be back into the circle of action if they got more than half that distance near the 

 old position in foraging, and would have to return to the old place. But this only happens 

 if the old position is less than sis kilometers away from the new. We must, therefore, 

 accept something near three kilometers as the boundary for this circle of action for this 

 force. " (Bethe, 1. c, p. 89.) 57 



I believe that the foregoing, and likewise in many other of his observations, Bethe 

 furnishes such excellent proof df the existence of memory for location that one can 

 hardly wish anything better. But Bethe supposes "a force unknown to us, " with which 

 we do not know what to do, which offers support for every investigation. Under this 

 head I must depend more strictly upon Bethe 's work in order at the same time to point 

 out the errors in the chapter, "How do Bees Find the Hive?" (Bethe, 1. c, p. 72.) 



THE "PATHS" OF BEES AND THEIR DIRECTION. 



If the bee-hives are placed on an open heath, with no elevations such as trees or bushes, 

 the particular kind of flight toward and away from the hive may be studied, undisturbed 

 by local conditions. In August, 1898, I had opportunity to prove this condition on a 

 moor in the neighborhood of Oldenburg, corroborating entirely my earlier experiences. 



The colonies were established on the moor by the bee-keeper shortly before the buck- 

 wheat-flow. The hive-entrances faced the east. On the first day the flight was weak, for 

 as yet there was nothing to gather. The bees flew out irregularly in smaller or larger 

 circles in all directions. There was nothing to be seen yet of " a path. ' ' M Great buckwheat- 

 fields stretched toward the north as well as to the south. When the flowers opened, the 

 mode of flight changed. Part of the bees flew from a point close to the entrance, sharply 



57 The "unknown force" must act at much greater distances under certain conditions, for 'other 

 observations show that bees have flown five, six, or even over seven kilometers further under extraor- 

 dinary circumstances. (See Bienenzeitung, X., No. 14; ditto III.. No. 9, Dzierzon; Le Rucher, Amiens, 

 1876,* IV., p. 30). In these cases there was no forage near at hand. According to Dzierzon, some bees 

 under these circumstances scented a large "hundred-acre" rape-seed field which lay far outside their 

 usual circle of flight. Roth, the* leader of the Baden school for bee-keepers, in Durlach, observed that 

 some of his bees returned in thirty minutes with full loads from a buckwheat-field six kilometers away. 

 Granting that Roth's bees flew to the buckwheat-field from the south, there is no reason for thinking 

 that bees from an apiary at the same distance toward the north had not hastened to this same nectar 

 supply. Now if, for experiment, a colony should be taken from the southern apiary to the northern 

 one, then they fly south to the buckwheat-field, and there, coming into the field of action, would again 

 return to the southern apiary. The "unknown force" would reach twelve kilometers in this very possible 

 case. If it be asked from what distance bees can find their way back, the answer can not be made in 

 kilometer measurements, for it depends upon whether the bees are in their, flight or orientation (see the 

 same) or in their search for food have flown to greater oi* less distances, Tipon the definite direction of 

 the forage and the general orientation. 



58 "It is well known that, in front of the entrance to a strong colony, there is always a long dark 

 cloud formed by the bees constantly going back and forth." (Bethe, p. 75.) This Is Bethe' s "bee-path." 



