ANATIDJE THE SWANS, GEESE, AND DUCKS.' 115 



Chen hyperborea nivalis KIDOW. Proc. Biol. Soc. Wash, ii, 1884, 107; Man. N. Am. B. 



1887. 115.-A. O. U. Check List, 1886, No. 169a. 

 Tadorna nivea BBEHM, Yog. Deutschl. 1831, 854. 



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

 tween McKenzie Eiver and Hudson's Bay; migrating south in winter through eastern 

 United States, including Mississippi Valley, to the Gulf coast, even reaching Cuba; occa- 

 sional or accidental in the Bermudas. 



SDISSP. CHAE. Entirely similar to G. hyperborea except in size, being considerably 

 larger; youug somewhat darker in color than in true C. hyperborea? 



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 larger race of the Snow 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 equal numbers. Farther eastward, however, 

 particularly along the Atlantic coast, the larger form is decidedly 

 the prevailing one, while west of the Rocky 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 

 points along the coast farther south. 



GENUS ANSEB, BRISSON. 



Anser BBISS. Orn. i, 1760, 261. Type, Anas anser LiNN..=J.. 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 tomia less divergent, etc. In fact, 

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

 larger species of Branta (ccmadensis and hutchinsii). The type 

 of the genus, however, A. (emereus 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 gambeli HARTLAUB). The same 

 species occurs also in Europe in a representative form the A. 

 albifrons 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. 



