CLANGULA.— NOMONYX. 227 



all shy, this species is difficult to procure, as it dives at the flash of a gun and 

 is extremely rapid in its movements. The food consists of fish, molluscs, freshwater 

 plants, &c. The flesh is much esteemed by some people as an article of food. 



Subfam. EBISMATUBINM. 



This subfamily comprises the stiff"-tailed Diving-Ducks, which are closely allied to 

 the Fulignlinse, but differ in having the tail-feathers narrow and very rigid, as is pointed 

 out by Count Salvador!. 



NOMONYX. 



Nomonyx, Eidgway, Pr. U. S. Nat. Mus. iii. p. 15 (1880) ; Salvad. Cat. Birds Brit. Mus. xxvii. 

 p. 438 (1895). 



This genus, represented by a single Tropical-American species, may be distinguished 

 from most of the Diving-Ducks by the narrow tail-feathers, which are also very stiff. 

 From Erismatura it differs in having the nail of the bill perpendicular. 



1. Komonyx domiuicus. 



Anas dominica, Linn. Syst. Nat. i. p. 201 '. 



Erismatura dominicus, Scl. P. Z. S. 1857, p. 206 'j 1860, p. 254*; Lawr. Mem. Bost. Soc Nat. 



Hist. p. 316*; Scl. & Sak. P. Z. S. 1876, p. 405 '. 

 Nomonyx dominicus, A. O. TJ. Check-l. N. Amer. Birds, 2nd ed. p. 60 ° ; Salvad. Cat. Birds Brit. 



Mus. xxvii. p. 438 ' ; Salvad. & Festa, Boll. Mus. Zool. Torino, xiv. no. 339, p. 13 ^ 



Supra niger, plumis singulis castaneo late marginatis ; alls brunnescenti-nigris, tectricibus majoribus et 

 dimidio externo basali secundariorum extimorum albis, speculum alare formantibus ; rectricibus nigris ; 

 capita nigro ; •coUo saturate castaneo, pectore pallidiore, abdomine albicanti-fulvo ; hypoehondriis nigris ; 

 maxilla et area nuda oculari cyaneis, ilia nigro apicata ; mandibula rufeseenti-alba, ad apieem nigra ; 

 mento nudo nigro ; pedibus brunneis, tarso extus et digitis externis saturatioribua. Long, tota circa 15-0, 

 alse 5"7, caudae 4-0, culm. 1"25, tarsi 1"15. (Descr. maris adulti ex Peru. Mus. nostr.) 



5 . Snpra saturate brunneus, fulvo maculatus ; alis sicut in mari coloratis, sed tectricibus alarum medianis 

 et majoribus fulvo maculatis ; cauda nigricante j pileo et capitis lateribus saturate brunneis ; supercilio 

 angusto et fascia latiore lorali ad occiput extensa fulvis ; corpore subtus brunneo, plumis singulis fulvo 

 vel albido marginatis, quasi marmoratis ; mento et gutture paUide fulvis ; coUo fulvo, brunneo maculate : 

 rostro brunneo, apice nigro. Long, tota circa 14-0, alae 5"6, caudae 3-8, culm. 1"2, tarsi l-l. (Descr. 

 feminse adultae ex Sarayacu, Ecuador. Mus. nostr.) 



Juv. feminse adultae similis, sed gastrasi plumis basaliter pallidioribus. 



Hah. North Ameeica, Gulf Coast to the Lower Eio Grande ; accidental in Wisconsin 

 and on Lake Champlain, Massachusetts ^. — Mexico, Jalapa, Vera Cruz [Salle ^ ^), 

 Tepic {Grayson^); Guatemala'^; Panama, Veragua (-4rce ^ ^), Laguna de Pita 

 {Festa ^). — Tkopical America generally, south to Chile and Argentina ^ ; West 

 Indies ^ 



The Masked Duck has been recorded from various widely separated localities in 



29* 



