ANATID.i:— THK SWANS, (JEESIO, AND DUf'KS/ 115 



Chen hyperborea nivalis RrDOW. Proc. Biol. 8oc. Wash, ii, 1881, 107; Man. N. Am. B. 

 1887, 115.— A. O. U. Chock List, 188G, No. 16'Jo. 

 Tadorna nivea Bbkhm. Vog. Deutschl. 1831, 8.54. 



Hab. Eastern North America; breeding grounds unknown, but probably region be- 

 tween MfKonzie Rivor and Hudson's Bay; migrating .south in winter through eastern 

 United States, including Mississii>pi Valley, to the Gulf coast, even reaching Cuba; occa- 

 sional or accidental in the Bermudas. 



8UIJSP. Chab. Entirely similar to V. hypprbnrpa except in size, being considerably 

 larger; young somewhat darker in color than in true C. fiviierborea? 



Total length, about 30.00-38.00; wing. 17.35-17.50 (17.42); culmen, 2.55-2.70(2.63); tarsus, 3.15- 

 3,50 (3.28) ; middle toe, 2.60-2.80 (2.70). 



This is simply a larp:er race of the vSnow Goose, and occurs 

 with the smaller form throughout the Mississippi Valley during 

 its migrations. Mr. Nelson is of the opinion that in Illinois the 

 two occur in about e(]ual numbers. Farther eastward, however, 

 particularly along the Atlantic coast, the larger form is decidedly 

 the prevailing one, while west of the Rooky Mountains it prob- 

 ably does not occur at all, though the smaller race is abundant 

 there. 



According to Mr. Boardman, it is common during migration 

 in eastern Maine, and it is said to be more or less common, 

 according to the locality and other circumstances, at various 

 ])oints along the coast farther south. 



Genus ANSER Brisson. 



Anser Briss. Orn. i, 1760, 261. Type, Anas anser Linn.,=^. cinereus Meteb. 



Gen. Chab. Bill much weaker or less swollen than in Chen (depth through base less 

 than half the length of the culmen); plumage never white,* nor with white head, nor 

 bluish wing-coverts. 



This genus differs from Chen chiefly in the form of the bill, 

 which is much less robust, more depressed terminally, the nails 

 thinner and less arched, the toniia less divergent, etc. In fact, 

 the bill of some species is quite identical in form with that of 

 larger species of Branta {canadensis and kittcMnsii) . The type 

 of the genus, however, A. {cinereus Meyer), has the bill decid- 

 edly approximating to that of Chen, the commissure gaping 

 quite widely. Only one species occurs in America, the common 

 White-fronted Goose {Anser gambell Hartjlaub). The same 

 species occurs also in Kurope in a representative form — the .4. 

 alhifron^i Gmel. The difference between them is chiefly one of 

 size, the American bird being decidedly the larger. Another 



* Except sometimes in species which have been long domesticated. 



