258 THE WONDERS OF INSTINCT 



A suspicion occurs to me, a suspicion aroused by my 

 attentive examination of the narrow tubes. All, what- 

 ever the number of their inmates, are carefully plugged 

 at the opening, just as separate tubes would be. It might 

 therefore be the case that the narrow gallery at the back 

 was looked upon by the Osmia not as the prolongation 

 of the large front gallery, but as an independent tube. 

 The facility with which the worker turns as soon as she 

 reaches the wide tube, her liberty of action, which is now 

 as great as in a doorway communicating with the outer 

 air, might well be misleading and cause the Osmia to 

 treat the narrow passage at the back as though the wide 

 passage in front did not exist. This would account for 

 the placing of the female in the large tube above the 

 males in the small tube, an arrangement contrary to her 

 custom. 



I will not undertake to decide whether the mother 

 really appreciates the danger of my snares, or whether 

 she makes a mistake in considering only the space at her 

 disposal and beginning with males, who are liable to re- 

 main imprisoned. At any rate, I perceive a tendency to 

 deviate as little as possible from the order which safe- 

 guards the emergence of both sexes. This tendency is 

 demonstrated by her repugnance to colonizing my narrow 

 tubes with long series of males. However, so far as we 

 are concerned, it does not matter much what passes at 

 such times in the Osmia's little brain. Enough for us 

 to know that she dislikes narrow and long tubes, not be- 

 cause they are narrow, but because they are at the same 

 time long. 



