OEBER ANSERES. 83 



Genus NOMONYX Ridgway. 



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

 orig. desig., Anas dominica Linn^us. 



Nom6nyx dominicus (I..inn^us). Masked Duck. [168.] 



Anas dominica LinnjBus, 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 ANSERINiE. Geese. 



Genus CHEN Boie. 



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

 Pallas. 



StTBGBNUS CHEN. 



Chen hyperboreus (Pallas). 



Range. — Arctic North America, south in winter to southern United 

 States and Mexico. 



o. Chen hyperboreus hyperboreus (Pallas). Snow Goose. [169.] 



Anser hyperhoreiMs 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.) 



