°1913 I'liii.ur , Mii/rnlion mitt I'trindic Accuracy. 191 



BIRD MIGRATION FROM THE STANDPOINT OF ITS 

 PERIODIC ACCURACY. 



i',v JOHN C. PHILLIPS. 



0] i inn i confess to ;i feeling of trepidation on entering into 

 such ;i dangerou held of discussion as bird migration, especially 

 in its theoretical aspect, for perhaps no scientific subject has been 

 o Hooded with wild speculation, dogmatic assertions and poetical 

 fancy. This is natural, because the facts cannol fail to come to 

 the notice of every lover of nature, and their aesthetic quality 

 makes them attractive material for thought and discussion. 



Bird migration touches many interesting provinces of science, 

 such ;is zoogeography, geology, meteorology, evolution and com- 

 parative psychology. What has recently excited the writer's 

 curio it \ is i he meaning of t he time sense of certain species of birds, 

 e pecially where such an accurate sense does not seem to be war- 

 ranted; in ;i word, where it seems more highly developed than is 

 compatible with adaptive necessity. 



In the pasl decade many of the facts of migiation have become 

 common knowledge, but when these facts are completely grasped, 

 and even when the movements of the individual bird have been 

 thoroughly studied, the great problem of migration is likely to 

 remain as much unsolved as ever, for the sense; on which distant 

 orientation depends, and the instinct which starts the travellers 

 are beyond the reach of our present methods of investigation. 

 Instinct itself i> of course the fundamental problem, a problem as 

 deep and obscure as any in tin; realm of philosophy. BergSOn 

 says: " The intellect is characterized hi/ a natural inability to com- 

 prehend life. Instinct on the contrary is moulded on the very 

 form of life. While intelligence treats everything mechanically, 

 instinct proceeds so to speak organically. If the consciousness 

 that slumbers in it should awake, if it were wound up into knowl- 

 edge, instead of being wound off into action, if we could ask and it 

 could reply, it would give up to US the most intimate secrets of 



life."' 



' Bergson, Creative Evolution, i>. 165. 



