60 CHECK-LIST OF NORTH AMERICAN BIRDS. 
Genus NOMONYX Ripeway. 
LNVomonyx Ripew. Pr. U.S. Nat. Mus. III. 1880, 15. Type, Anas 
dominica LINN. 
[168.] Nomonyx dominicus (Linv.). 
Masked Duck. 
Anas dominica Linn. S. N. ed. 12, 1766, 201. 
LVomonyx dominicus Rrpew. Pr. U.S. Nat. Mus. III. 1880, rs. 
PRGroC 620, RiGsn C742, | 
Groc. Dist.— Tropical America in general, including West Indies, 
north on the Gulf coast to the Lower Rio Grande; accidental in 
eastern North America (Wisconsin; Lake Champlain; Massachusetts). 
SuBFAMILY ANSERINAG. GEEsE. 
Genus CHEN Bor. 
Chen Bots, Isis, 1822, 563. Type, Anser hAyperboreus PALL. 
169. Chen hyperborea (PALL.). 
Lesser Snow Goose. 
Anser hyperboreus PAuu. Spicil. Zool. VI. 1769, 25. 
Chen hyperborea Botr, Isis, 1822, 563. 
[B—, C 480a, R 5914, C 696.] 
Groc. Dist.— Pacific coast to the Mississippi Valley, breeding in 
Alaska; south in winter to southern Illinois and southern California ; 
casually to New England. Northeastern Asia. 
169 a. Chen hyperborea nivalis (Forst.). 
Greater Snow Goose. 
Anas nivalis ForstTER, Philos. Trans. LXII. 1772, 413. 
Chen hyperboreus nivalis Ripcw. Pr. Biol. Soc. Wash. II. 1884, 
107. 
[B 563, C 480, R 591, C 695.] 
Geoc. Dist.— North America, breeding far north (east of Macken- 
zie basin) and migrating south in winter, chiefly along the Atlantic 
coast, reaching Cuba. 
