NATURE'S CRAFTSMEN 



an odd way of meeting these intruders when he is on 

 guard. He turns tail, and pushes the point of his 

 abdomen into the opening, an effective though seem- 



DIAGRAM OP THE NESTING BURROW OF IIALICTUS PRUINOSUS, A 

 SOLITARY BEE 



ingly not a valiant mode of defence. But, indeed, Sir 

 Halictus is not to be blamed, for nature has denied him 

 the fighting weapons with which the female is endowed; 

 for in this sphere of life of which we are writing real 

 Amazons are the rule, not the exception. 



One of the most dangerous and annoying of the 

 Halictine foes is a small parasitic fly, Phora cara. This 

 insect, on maternal duty bound, following the same 

 instinct that sends the mother bee to the flowery fields, 

 loiters at the Halictvis gate. Now comes thither the 

 burdened bee. She pauses a second at the door to pass 

 the marital sentinel's challenge. It is enough! That 

 pause is fatal. Swiftly the dipterous ovipositor thrusts 

 a parasitic egg into the pollen mass, and the mother 

 herself bears to her offspring's cradle the germ of death. 

 So goes on to-day, and day by day forever, the old 

 story of how the Trojans themselves brought into the 

 walls of Troy the armed destroyers of their town! 



To these alien parasites one must add sundry species 

 of guest bees, who rear their offspring at the expense of 

 the hard working Halictus and Andrena. They bear 



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