CHAPTEE IV. 

 THE MIGRATION OF BIRDS.* 



To the field student tlie season of migration is the 

 most interesting of the year. The bird-life of a vast 

 area then passes in review before him. Though living 

 in a temperate region, he may see birds whose summer 

 home is within the Arctic Circle, whose winter haunts are 

 in the tropics. Who can tell what bird he may find in 

 the woods he has been exploring for years ? 



The comparative regularity with which birds come 

 and go gives an added charm to the study of migration. 

 Their journey is not a " helter-skelter " rushing onward, 

 but is like the well-governed march of an army. We 

 feel a sense of satisfaction in knowing when we may ex- 

 pect to greet a given species, and a secret elation if we 

 succeed in detecting it several days in advance of other 

 observers. We study weather charts, and try to foretell 

 or explain those great flights or " waves " of birds wliicli 

 are so closely dependent upon meteorologic conditions. 



* Read Allen, Scribner's Magazine, vol. xxii, 1881, pp. 932-938, 

 Bulletin of Nuttall Ornithological Club (Cambridge, Mass.), vol. v, 

 1880, pp. 151-154. Scott, ibid., vol. vi, 1880. pp. 97-100, Brewster, 

 Memoirs of Nuttall Ornithological Club, No. 1, pp. 22. Cooke and 

 Merriam, Bird Migration in the Mississippi Valley (Washington, 1888). 

 Chapman, The Auk (New York city), vol. v, 1888, pp. 37-39 ; vol. xi, 

 1894, pp. 12-17. Loomis, ibid., vol. ix, 1892, pp. 28-39: vol. xi, 1894, 

 pp. 26-39, 94-117. Stone, Birds of Eastern Pennsylvania and New 

 Jersey, pp. 15-28. 



