1 8 Introduction 



Blackbird, and others of the hardy troop that face the rigors 

 of this early season. About the time the first cluster of pale 

 blue Hepatica blossoms is found nestling among the brown 

 leaves, a number of birds have appeared, and we ask ourselves 

 the question, What impulse brings the birds home again? 



We are face to face, now, with the great world-problem 

 of bird migration. But there is no answer, that we know, 

 under the azure dome of our April heaven. Various theories 

 have been advanced by learned ornithologists of Europe and 

 America, but it is generally acknowledged that none of them 

 has found the right key, and the door to the mystery still 

 remains unlocked. It is not the purpose of this work to 

 enter upon this discussion, or even to summarize the theories 

 already presented; but as all mysteries have their charm, and 

 the riddle of bird migration is one of the most alluring of 

 them all, it seems not out of place to call the reader's attention 

 to the movement of the birds, which, twice a year, goes on 

 about us. 



In May come the Warblers (Mniotiltidae), the daintiest, 

 brightest colored, and the least known family of birds. They 

 move in "waves," or companies, often composed of several 

 hundred individuals and a number of species. The gentle 

 slopes of the Hudson Valley in this part of the State, where 

 small woods and second growth abound, and especially the 

 little ravines that are found here and there, north and south of 

 Albany, are well adapted to the Warblers. I speak of the 

 Mniotiltidae as being the least known family of birds; by 

 this I mean that Farmer Babcock, or the Dweller in Cities, 

 may never have seen or heard of them, but the careful bird 

 student knows them and appreciates their beauty. 



