THE OSMIiE 227 



birth of my insects, that is to say, their first seeing the 

 Hght, their emerging from the cocoon, should take place 

 on the spot where I propose to make them settle. Here 

 there must be retreats of no matter what nature, but of a 

 shape similar to that in which the Osmia delights. The 

 first impressions of sight, which are the most long-lived 

 of any, shall bring back my insects to the place of their 

 birth. And not only will the Osmiae return, through the 

 always open windows, but they will also nidify on the 

 natal spot, if they find something like the necessary con- 

 ditions. 



And so, all through the winter, I collect Osmia-cocoons 

 picked up in the nests of the Mason-bee of the Sheds; 

 I go to Carpentras to glean a more plentiful supply in 

 the nests of the Anthophora. I spread out my stock in a 

 large open box on a table which receives a bright 

 diffused light but not the direct rays of the sun. The 

 table stands between two windows facing south and 

 overlooking the garden. When the moment of hatching 

 comes, those two windows will always remain open to 

 give the swarm entire liberty to go in and out as it 

 pleases. The glass tubes and reed-stumps are laid here 

 and there, in fine disorder, close to the heaps of cocoons 

 and all in a horizontal position, for the Osmia will have 

 nothing to do with upright reeds. Although such a pre- 

 caution is not indispensable, I take care to place some 

 cocoons in each cylinder. The hatching of some of the 

 Osmiae will therefore take place under cover of the gal- 

 leries destined to be the building-yard later ; and the site 

 will be all the more deeply impressed on their memory. 



