WASPS, SOCIAL AND SOLITARY 



of buildings. We have found T. rubrocinctum taking 

 advantage of the face of a straw-stack that had been 

 cut off smoothly as the cattle were fed through the win- 

 ter. The same power of adaptation is shown by Fabre's 

 experiment with Osmia, in which he took two dozen 

 nests in shells from a quarry, where the bees had been 

 nesting for centuries, and placed them in his study 

 along with some empty shells and some hollow stems. 

 When the bees came out, in the spring, nearly all of 

 them selected the stalks to build in as being better suited 

 to their use than the shells. All of these changes are 

 intelligent adaptations to new modes of life, serving 

 to keep the species in harmony with its surroundings. 

 The same thing may be seen when a number of social 

 wasps work together to replace the roof of their nest 

 when it has been torn off. 



An instance of the second class is seen in one of our 

 examples of Pompilus marginatus. This species, while 

 searching for a nesting-place, leaves its spider lying on 

 the ground or hides it under a lump of earth, in either 

 of which positions the booty is subject to the attacks 

 of ants; the wasp -in question improved upon the custom 

 of her tribe by carrying the spider up into a plant and 

 hanging it there. We have now and then seen a queen 

 of Poiistes fusca occupy a comb of the previous year 



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