The Mason-bees 



If any doubts remained as to the incapacity 

 of the Mason-bee of the Walls to know her 

 nest other than by the place which the pebble 

 occupies on the ground, here is something to 

 remove them : for the nest of one Mason-bee, 

 I substitute that of another, resembling it as 

 closely as possible in respect to both masonry 

 and storage. This exchange and those of 

 which I shall speak presently are of course 

 made in the owner's absence. The Bee set- 

 tles without hesitation in this nest which is 

 not here, but which stands where the other 

 did. If she was building, I offer her a cell in 

 process of building. She continues the ma- 

 sonry with the same care and the same zeal as 

 if the work already done were her own work. 

 If she was fetching honey and pollen, I offer 

 her a partly-provisioned cell. She continues 

 her journeys, with honey in her crop and 

 pollen under her belly, to finish filling an- 

 other's warehouse. The Bee, therefore, does 

 not suspect the exchange; she does not 

 distinguish between what is her property and 

 what is not; she imagines that she is still work- 

 ing at the cell which is really hers. 



After leaving her for a certain time in pos- 

 session of the strange nest, I give her back 

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