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turbed or displeased, would hiss almost exactly like a goose. If 

 a canary alighted on his cage, the bobolink would thrust out his 

 head toward the intruder and hiss it off. Once, in a field, I 

 heard a bobolink sing half the most common song of the Amer- 

 ican goldfinch. Last summer I used often to walk across Portage 

 High Bridge to the Letchworth woods, to listen to a remarkably 

 fine-voiced wood-thrush, that in every song interjected the long 

 plaintive call of the wood-pewee. The effect was unique and 

 surprising. 



To those interested in the psychical or reason development of 

 birds, this subject possesses increased interest. It is quite gen- 

 erally conceded that birds are not only the most interesting, but 

 in some respects the most highly organized, especially in form, 

 color, voice, and power of locomotion, of any of the so-called 

 lower animals. In some directions, too, they are the most intel- 

 ligent. Not only does their heredity count for much, but their 

 experience is a large factor in shaping and modifying their man- 

 ner of life. Many of them are quick to take advantage of any 

 extraneous circumstances by which their conditions may be bet- 

 tered. How many cases come under our notice in which cause 

 and effect plainly enter into their calculation. Several species 

 throw out sentinels to guard against surprise, and these have 

 signal notes well understood by all. They learn to avoid locali- 

 ties that are extra dangerous, and often gather in large numbers 

 where safety is assured. They profit both by experience and 

 example, often modifying their nesting habits, and adopting new 

 methods for protection. What subterfuges our native birds 

 make use of to mislead and baffle larger birds of prey. On the 

 contrary, the English sparrows, mostly denizens of villages and 

 cities, and not often having been exposed to the dangers that 

 beset the birds of forests and fields, fall an easy prey to the 

 smaller hawks, owls and shrikes that occasionally find their way 

 among them. They know well enough how to avoid the dan- 

 gers of city life, and are seldom caught napping by cat or boy. 



As the birds and their eggs are so preyed upon by such a 

 multiplicity of enemies, perpetuation and self-defense become 

 3 



