Instinct and Discernment 



tain the goal. But the free lodging offered 

 by chance varies exceedingly in hygienic con- 

 ditions, in shape and in capacity. Instinct, 

 which does not choose, which docs not con- 

 trive, would, if it were alone, leave the insect's 

 existence in peril. To help her out of her 

 predicament, in these complex circumstances, 

 the Osmia possesses her little stock of dis- 

 cernment, which distinguishes between the dry 

 and the wet, the solid and the fragile, the 

 sheltered and the exposed; which recognizes 

 the worth or the worthlessness of a site and 

 knows how to sprinkle it with cells according 

 to the size and shape of the space at disposal. 

 Here, slight industrial variations are neces- 

 sary and inevitable; and the insect excels in 

 them without any apprenticeship, as the ex- 

 periment with the native Osmia of the quar- 

 ries has just proved. 



Animal resources have a certain elasticity, 

 within narrow limits. What we learn from 

 the animals' industry at a given moment is 

 not always the full measure of their skill. 

 They possess latent powers held in reserve for 

 certain emergencies. Long generations can 

 succeed one another without employing them; 

 but, should some circumstance require it, sud- 



211 



