Reflections upon Insect Psychology 



just described. To relate them would be mere 

 repetition; I pass them over for the sake of 

 brevity. 



The renewal of a test Is not sufficient: we 

 must also vary our test. Let us, then, examine 

 the insect's intelligence from another point of 

 view, that of the introduction of foreign bo- 

 dies into the cell. The Mason-bee is a house- 

 keeper of scrupulous cleanliness, as indeed are 

 all Hymenoptera. Not a spot of dirt is per- 

 mitted in her honey-pot; not a grain of dust 

 is tolerated on the surface of her mixture. 

 And yet, while the jar is open, the precious 

 •Bee-bread is exposed to accidents. The work- 

 ers in the cells above may inadvertently drop 

 a little mortar into the lower cells; the owner 

 herself, when working at enlarging the jar, 

 runs the risk of letting a speck of cement fall 

 Into the provisions. A Gnat, attracted by the 

 smell, may come and be caught In the honey; 

 brawls between neighbours who are getting 

 Into each other's way may send some dust fly- 

 ing thither. All this refuse has to disappear 

 and that quickly, lest afterwards the larva" 

 should find coarse fare under its delicate man- 

 dibles. Therefore the Mason-bees must be 

 able to cleanse the cell of any foreign body. 

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