The Halicti ; the Portress 



soon as the new arrival has entered, the trap 

 rises back into its place, almost level with the 

 ground, and closes the entrance anew. The 

 same thing happens when the insects go out. 

 At a request from within, the trap descends, 

 the door opens and the Bee flies away. The 

 outlet is closed forthwith. 



What can this valve be which, descending 

 or ascending in the cylinder of the pit, after 

 the fashion of a piston, opens and closes the 

 house at each departure and at each arrival? 

 It is an Halictus, who has become the portress 

 of the establishment. With her large head, 

 she makes an impassable barrier at the top of 

 the entrance-hall. If any one belonging to 

 the house wants to go in or out, she "pulls the 

 cord," that is to say, she withdraws to a spot 

 where the gallery becomes wider and leaves 

 room for two. The other passes. She then 

 at once returns to the orifice and blocks it 

 with the top of her head. Motionless, ever 

 on the look-out, she docs not leave her post 

 save to drive away importunate visitors. 



Let us profit by her brief appearances out- 

 side to take a look at her. We recognize in 

 her an Halictus similar to the others, who are 

 now busy harvesting; but the top of her head 



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