The Bembex 



two at the back a little wide apart, while the 

 front ones alternately scratch and sweep the 

 shifting sand. The precision and quick- 

 ness of the performance could not be greater 

 if the circular movement of the tarsi were 

 worked by a spring. The sand, shot back- 

 wards under the abdomen, passes through 

 the arch of the hind-legs, gushes like a fluid 

 in a continuous stream, describes its para- 

 bola and falls to the ground some seven or 

 eight inches away. This spray of dust, 

 kept up evenly for five or ten minutes at a 

 time, is enough to show the dazzling rapid- 

 ity of the tools employed. I know no other 

 example of this swiftness, which neverthe- 

 less in no way detracts from the easy grace 

 and the free movement of the insect, as it 

 advances and retires first on this side, then 

 on that, without discontinuing its parabolic 

 streams of sand. 



The soil excavated is of the lightest kind. 

 As the Wasp digs, the sand near by slips 

 back and fills the cavity. Amongst the rub- 

 bish that falls are tiny bits of wood, decayed 

 leaf-stalks and particles of grit larger than 

 the rest. The Bembex takes them up in her 

 mandibles and carries them away, moving 

 backwards as she goes; then she returns to 

 275 



