ORDER ANSERES. 83 



GENUS NOMONYX RIDGWAY. 



Nomonyx RIDGWAY, Proc. U. S. Nat. Mus., Ill, 1880, 15. Type, by 

 orig. desig., Anas doininica LINNAEUS. 



Nomonyx dominicus (LiNN^us). Masked Duck. [168.] 



Anas doininica LINN^US, Syst. Nat., ed. 12, I, 1766, 201. (Santo 

 Domingo.) 



RANGE. Tropical America. Breeds in the West Indies and in 

 eastern South America to central Argentina; occurs rarely and locally 

 from the lower Rio Grande in Texas south to Mexico, Guatemala, 

 and western South America; recorded also from Wisconsin, Massa- 

 chusetts, Vermont, and Maryland. 



SUBFAMILY ANSERDUE. GEESE. 



GENUS CHEN BOIE. 



Chen BOIE, Isis, X, 1822, 563. Type, by monotypy, Anser hyperboreus 

 PALLAS. 



SUBGENUS CHEN. 



Chen hyperboreus (PALLAS). 



RANGE. Arctic North America, south in winter to southern United 

 States and Mexico. 



a. Chen hyperboreus hyperboreus (PALLAS). Snow Goose. [169.] 



Anser hyperboreus PALLAS, Spic. Zool., I, Fasc. vi, 1769, 25. (North- 

 eastern Siberia.) 



RANGE. North America. Breeds from mouth of the Mackenzie east 

 probably to Coronation Gulf and Melville Island; occurs on the Arctic coast 

 of northeastern Asia, but not known to breed there; winters from southern 

 British Columbia, southern Colorado, and southern Illinois south to northern 

 Lower California, central Mexico (Jalisco), Texas, and Louisiana, and on the 

 Asiatic coast south to Japan; generally rare in eastern United States. 



6. Chen hyperboreus nivalis (J. R. FORSTER). Greater Snow Goose. [169a.] 

 Anas nivalis FORSTER, Philos. Trans., LXII, 1772, 433. (Severn River, 

 Hudson Bay, Canada.) 



