IN TROD UC TION. XXI 



group of idle fellows, whose only idea of life is amuse- 

 ment and sustenance. 



Between the sexes of the Ducks and Mergansers great 

 difiference in the color of the plumage is observable, 

 males and females rarely resembling each other either in 

 the hues or markings of their feathers, but among the 

 Sw^an and Geese the sexes are similar. One characteris- 

 tic mark of many species of Ducks is the speculum, or 

 conspicuous spot on the wing formed by the coloration, 

 often metallic, of the terminal portion of the secondaries. 

 This sometimes serves to identify the species, especially 

 in the case of the female, and is frequently of brilliant 

 hues in both sexes, though brighter always in the male. 



The various groups into which the Family has been 

 divided are closely united, and although there are many 

 artificial sections easily recognized among tliem, known 

 as genera, yet all the species are more or less nearly re- 

 lated, and the Family is a very compact one, and easily 

 distinguished from all others. 



The Wild Fowl are migratory; some, indeed the great 

 majority, — comprising all those breeding in boreal 

 regions, — pass over an immense extent of the continent 

 twice a year, spring and autumn. On such occasions 

 they proceed in great flocks, usually some veteran bird 

 leading the way, guided by the experience derived from 

 travels of many years. The large species, Swan and 

 Geese, journey in a V-shaped formation; Ducks also fre- 

 quently adopt this same method, but they often also 

 travel in a curved line, occasionally even all abreast. 

 This last formation is not continued for any great dis- 

 tance. The few species inhabiting the temperate por- 

 tions of North America, and which breed there, make 

 very brief migrations, if indeed any at all. North 

 America at one time probably contained more Wild Fowl 



