AN ISLAND SETTLEMENT 



half a dozen places before she was satisfied, and spinolae 

 is quite as difficult to please. 



When, at last, the right place is found, the labor of 

 excavation is carried on vigorously. The mandibles are 

 used for loosening the earth, and for lifting, but the 

 greater part of the work is done with the first pair of legs, 

 the tarsi of which are doubled up while the dirt is swept 

 out with the brush of stiff spiny hairs on the second joint. 

 This attitude gives them a very comical aspect, making 

 them look as if they were sweeping with their elbows. 

 They sometimes lie far over to one side while loosening 

 the earth with their mandibles. While digging, the body 

 is held high by the straightening of the third pair of legs, 

 and the dirt comes out behind in a rapid stream, flying to 

 a distance of three or four inches. Before long the wasp 

 is lost to sight, but every few moments she comes back- 

 ing out, pushing behind her the dirt that she has dis- 

 placed below. In about fifteen minutes the nest is ready, 

 and the wasp turns her attention to scattering all the 

 dirt that has been thrown out, sweeping the ground 

 clean so that no sign of her work remains. We have 

 often speculated as to the meaning of the careful and 

 conscientious performance of this part of her task. With 

 the wasps that nest by themselves it is not easy to see 

 what enemy they are providing against in hiding the 



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