40 HYMENOPTERA 



its nests to the small boulders brought down and left by the 

 Ehone on the waste places of its banks. This habit afforded 

 Pabre an opportunity of removing the nests during the process 

 of construction, and of observing the effect this produced on the 

 architects. While a bee that had a nest partially constructed 

 was absent, he removed the stone and the nest attached to it from 

 one situation to another near at hand and visible from the 

 original site. In a few minutes the bee returned and went 

 straight to the spot where the nest had been ; finding its home 

 absent it hovered for a little while around the place, and then 

 alighted on the vacated position, and walked about thereon in 

 search of the nest ; being after some time convinced that this 

 was no longer there, it took wing, but speedily returned again to 

 the place and went through the same operations. This series of 

 manoeuvres was several times repeated, the return always being 

 made to the exact spot where the nest had been originally located ; 

 and although the bee in the course of its journeys would pass 

 over the nest at a distance of perhaps only a few inches, it did 

 not recognise the object it was in search of If the nest 

 were placed very near to the spot it had been removed from — 

 say at a distance of about a yard — it might happen that the bee 

 would actually come to the stone to which the nest was fixed, 

 would visit the nest, would even enter into the cell it had left 

 partially completed, would examine circumspectly the boulder, 

 but would always leave it, and again return to the spot where 

 the nest was originally situated, and, on finding that the nest 

 was not there, would take its departure altogether from the 

 locality. The home must be, for the bee, in the proper situation, 

 or it is not recognised as the desired object. Thus we are con- 

 fronted with the strange fact that the very bee that is able to 

 return to its nest from a distance of four kilometres can no 

 longer recognise it when removed only a yard from the original 

 position. This extraordinary condition of the memory of the 

 Insect is almost inconceivable by us. That the bee should 

 accurately recognise the spot, but that it should not recognise 

 the cell it had itself just formed and half-filled with honey-paste, 

 seems to us almost incredible ; nevertheless, the fact is quite con- 

 sistent with what we shall subsequently relate in the case of the 

 solitary wasp Bemhex. A cross experiment was made by taking 

 away the stone with the attached nest of the bee while the latter 



