CARPENTERS AND WOOD-WORKERS 103 



first bee of the brood escaped, and so on in inverse 

 order to their age with the entire brood. It .is 

 not surprising to learn from Fabre that this is not 

 the case. He found that as a fact the order in 

 which the eggs were laid had no relation of necessity 

 to the order in which the perfect insects emerged 

 from their cocoons. 



When one of the bees has completed its develop- 

 ment it tears open the cocoon that has contained 

 it, and then pierces the partition erected by its 

 mother between it and the next cell. Should it 

 chance to be the one nearest the entrance there is, 

 of course, no difficulty. It is free. But if its 

 egress is blocked by another cell, or more, it will 

 not violate the cocoon, but waits, cramped up but 

 patient, for days until the other has emerged in 

 front of it. It may, after thus waiting and feeling 

 the impulse of the work it has to do, strive to break 

 through the wood of the bramble- stem, or clear a 

 passage beside the cocoon, but it will die rather 

 than injure a cocoon it knows to be occupied by a 

 living pupa of its own race. If something has gone 

 wrong with one of the outer cells, so that emergence 

 from the inner ones is delayed more than a week 

 or two, they will probably all die. 



Fabre blocked such a tunnel with cocoons con- 

 taining dead specimens of the same species, and 

 found that in every case the emerging bees had no 

 scruple as to breaking through such cocoons : they 

 knew the inmates were dead. He then took a reed 

 that contained the cells of another species of Osmia 



