PREFACE 



The present work is intended to meet the wants of a large number of persons, 

 especially sportsmen, who are interested in birds and would like to know their names, 

 but often find it no easy task to identify them by the " bird books." To all such I 

 offer this Key, in which the species are arranged in groups according to size, and 

 believe it will enable any one unfamiliar with birds to identify with comparative ease 

 any species of our North American Anatida\ 



Birds vary so much in size that the length of any one specimen cannot be accepted 

 as a standard for others of the same species. The length measure is, nevertheless, 

 of value to enable us to form an approximate idea of the size of the bird. The length 

 of the wing is, however, much less variable, and is an important aid to the identifica- 

 tion of many species. In fact, the variation is so small and constant that, allowing 

 for possible extremes, they may be arranged in groups according to length of wing. 

 The identification of any species then becomes a very simple matter, as usually the 

 birds contained in each group are so few in number that characteristic differences in 

 each species are easily indicated. 



Let us assume, for example, we have before us a bird which we wish to identify. 

 We first measure the wing (see directions for measurements, illustrated, page 7), and 

 we find the wing measures 5.90 inches long. We now tiu'n to the " Index to Key," and 

 find that Group I. contains birds having the wing measuring from 5.50 to 6.50 inches 

 long. Turning to Group I., we find it contains two sections; Section 1 comprising 

 ducks having a hind toe without flap or lobe,* and Section 2 comprising ducks having 

 a flap on the hind toe. As our duck has a flap on its hind toe, it evidently belongs 

 to this section. We find Section 2 divided in two parts ; Part 1 with tail feathers 



* Many of the Anatince or River Ducks have a slightly flattened hind toe approaching a small flap, but it is 

 never large enough to confound them with the Fuliffulince or Sea Ducks, which have a LARGE well developed 

 lobe-like flap on the hind toe. 



