Instinct and Discernment 



observe that the enterprising invader, un- 

 like the Pelopaeus, never penetrates inside 

 our dwellings. The case of the conser- 

 vatory is an exception more apparent than 

 real: the glass building, standing wide open 

 throughout the summer, is to the Mason- 

 bee but a shed a little lighter than another. 

 There is nothing here to arouse the distrust 

 with which anything indoors or closed in- 

 spires her. To build on the threshold of 

 an outer door, to usurp its lock, a hiding- 

 place to her fancy, is all that she allows 

 herself; to go any farther is an adventure 

 repugnant to her taste. 



Lastly, in the case of all these dwellings, 

 the Mason-bee is man's free tenant; her in- 

 dustry makes use of the products of our own 

 industry. Can she have no other establish- 

 ments? She has, beyond a doubt; she pos- 

 sesses some constructed on the ancient plan. 

 On a stone the size of a man's fist, pro- 

 tected by the shelter of a hedge, sometimes 

 even on a pebble in the open air, I see her 

 building now groups of cells as large as a 

 walnut, now domes emulating in size, shape 

 and solidity those of her rival, the Mason- 

 bee of the Walls. 



The stone support is the most frequent, 

 though not the only one. I have found 

 165 



