EEISMATUEA.— MEKGANSEE. 229 



(Grayson^), Aguas Calientes {Richardson '^% Guanajuato {Buges^), Valley of 

 Mexico {Herrera^, Le Strange'^% Laguna de Chapuico, Puebla, Jalapa, Vera 

 Cruz {Ferrari-Perez ''), Oaxaca {Boucard ^) ; Guatemala, Duenas, Lake of Atitlan 

 {0. S.^^ i3j . Costa Rica, Irazu {v. Frantzius ^^). — Colombia ^^ ; West Ii^dies " ^^. 



The Euddy Duck inhabits the greater portion of North America, and is found 

 breeding throughout the temperate area of that Continent, as well as in Central 

 America. The species also occurs in Colombia, and is believed to breed there. In 

 Mexico, according to Herrera, the native name is " Yacatexoctli." We met with the 

 bird in Guatemala ^, breeding on the Lake of Duenas, where it was the only resident 

 species of the Anatidse. 



Salvin ^ writes : — " It is more easily procured than any of the other Ducks frequenting 

 the Lake, as its powers of flight render its escape less easy. Not but that it flies as 

 well as any other when once fairly started ; but it finds difl&culty in rising from ofi" 

 the water, so much so, that, by sailing down-wind towards a bird, it usually admits of 

 approach to within easy shooting-distance. Sometimes, however, it seeks safety by 

 diving ; and when such is the case, its powers in this respect are so great that escape 

 is almost certain to ensue. It builds in May, amongst the reeds on the margin of 

 the Lake, making a nest of the dead flag with a little down." The eggs are rough 

 in texture, of a dirty creamy-white colour. 



Subfam. MEEGINJE. 



The Mergansers, which are the representatives of this subfamily, are northern birds 

 which reach Central America only in winter. They differ from the other Diving-Ducks 

 noticed here in their narrower and more compressed bills, which are remarkable for 

 the tooth-like serrations along the edges of the mandibles. 



MERGANSER. 

 Merganser, Briss. Orn. vi. p. 230 (1760) ; Salvad. Cat. Birds Brit. Mus. xxvii. p. 471 (1895). 



The true Mergansers may be distinguished from Lophodytes by the conspicuous 

 tooth-like seiTations of both mandibles. The genus is a cosmopolitan one, and 

 though represented by seven species — three of which have a northern habitat — 

 resident forms are found within the tropics, of which M. brasilianus is an example. 

 One species only, M. americanus, visits Central America in winter. 



1. Merganser americanus. 



Mergus americanus, Cass. Pr. Acad. Philad. 1853, p. 187 ^ ; Allen, Bull. Amer. Mus. N. H. v. 

 p. 32' j A. O. U. Check-1. N. Amer. Birds, 2iid ed. p. 47'j Salvadori, Cat. Birds Brit. Mus. 

 xxvii. p. 477*. 



Interscapulio et Bcapularibus elongatis nigris ; dorso toto, uropygio et supracaudalibus cinereis ; tectricibus 

 marginalibus nigris, majoribus quoque basaliter nigris ; tectricibus primariorum et primariis nigricantibus ; 



