28 Instinct. 



xy for his individual welfare or that of the species. 

 It does this in many cases with almost the certain- 

 ty of the operations of the laws of inorganic nature. 

 Not more surely does the stone thrown into the 

 air come to the ground, or water seek a level, than 

 the bird knows its time for nesting and the materi- 

 al and fashion which mark the work of the species. 

 And when Instinct varies or is deceived, as some- 

 times happens, it is done according to some law of 

 the creature's being, by the introduction of some 

 new condition ; as the stone returning to the earth 

 may be turned from the curve Avhich gravitation 

 alone would give it, by the current of wind. 



Instinct begins its work by utilizing structure 

 and function of organs. Has the bird a gland for 

 the secretion of oil ? She knows instinctively how 

 to press the oil from the gland and apply it to the 

 feather. Has the rattlesnake the grooved tooth and 

 gland of poison ? He knows without instruction 

 how to make both structure and function most ef- 

 fective against his enemies. Has the silk-worm the 

 function of secreting the fluid silk ? At the proper 

 time, she winds the cocoon such as she has never 

 seen, as thousands before have done ; and thus 

 without instruction, pattern or experience, forms a 

 safe abode for herself in the period of transforma- 

 tion. Has the hawk talons ? She knows by in- 

 stinct how to wield them effectively against the 

 helpless quarry. 



But it is not structure and function alone that 

 call instinct into play. There are certain manifes- 

 tations of Instinct that are marvellous — manifesta- 



