INTELLIGENCE IN BIRDS. 121 



one generation to another. Many young birds left to 

 themselves, without example of the older ones, would 

 not go south at the approach of cold weather- unless by 

 accident. Those hatched too late to move with others 

 of their kind often wander about aimlessly until they 

 perish with the cold. Birds that are brought across the 

 ocean from countries where climate does not render a 

 change necessary do not fly south at the approach of 

 winter. The English sparrows survive by their extreme 

 hardiness, otherwise they would perish like other immi- 

 grants. The partial failure in the introduction of the 

 skylarks into this country is due solely to the lack of 

 knowledge on the part of the birds concerning the cli- 

 matic changes. They have not learned the necessity of 

 moving to lower latitudes, and not having the example 

 of their elders, nor the instinct transmitted from ances- 

 tors, they remain north in the fall and perish with the 

 cold. 



Tn nothing do the birds display greater sagacity or 

 show more clearly their exercise of reasoning powers 

 than in some of the phases of their migration. It is yet 

 one of the mysteries of nature how they find their way 

 back over a distance of thousands of miles, to the very 

 tree or stump or barn in ^vhich they nested the year 

 before. Do they remember familiar objects noted on 

 their southern journey, or do they remember only direc- 

 tion, and, like the honey bee, '' strike a bee line " towards 

 their destination ? The theory of '^ widening circles of 

 flight" cannot be true, as this would take them into 

 such extremes of heat and cold as to make it impossible: 



