BIRDS — ERISMATUEINAE — ERISMATURA ROBIDA. 



811 



Sub-Family ERISMATURINAE. 



The most prominent character of the Erismaturinae is found in the very rigid tail feathers 

 vitli tlie much ahhreviated coverts, which leave the greater portion of the tail exposed. Tliere 

 are peculiarities in the nail at the end of the hill in Erismatura not found in the other suh-families. 



ERISJIATURA, B o n a p . 



Ozyura, Bunap. Syn. 1828. Type Anca rubida. Sufficiently distinct from Oxyurus. ? Type Anas Icucocephala, Scop. 

 Erismatura, Bokap. Saggio, etc., 1832. 



Cn.— Bill broad, raflior liigh at the base, much dcpreseeJ, and bent upwards. Upper lateral angle of bill running hack on 

 the forehead Bouio disianoe; farther than the lower edge of the bill. Nostrils reaching to the middle of the bill, rnthor small. 

 Portion of nail seen from above very narrow and linear ; bent abruptly downwards and backwards at the tip so as to bo 

 invisible from the upper surface. Tarsi very short, scarcely more than one-third the long feet. Tail very stiff; of 18 feathers. 

 The coverts above and below very much abbreviated, so as to expose the greater part of the tail. The feathers narrow, 

 linear. The shafts very large, and channelled on the under surface near the base. Wings very short, and incurved at the end. 



Of this genus there are several species helonging to America, although but one is well 

 established as an inhabitant of the United States. Dr. Cabot, however, has recently announced 

 the occurrence of the E. dominica on Lake Champlain. 



Comparative measurements of species. 



ERISMATURA RUBIDA, Bo nap. 



Rnddy Duck. ' 



Jinas rubida, "Wilson, Am. Orn. VIII, 1814, 128, 130 ; pi. l.xjc.xi. 



.Inas (FttUsula) rubida, Bon. Obs. Wils. 1825, 268. 



FuUgula (Oxyura) rubida, BoN. Syn. 1828, 390. 



Fuli^ula (Gijmnura) rubida, Nuttall, Man. II, 1834, 426. 



FuUgula rubida, Sw. F. Bor. Am. II, 1831, 455.— Acd. Orn. Biog. IV, 1838, 326 ; pi. 343.— 1b. Syn. 288.— Ib. 



Birds Am. VI, 1843, 324 ; pi. 399. 

 £i-is7na/ura ru6i(/a, Bonap. List, 1838.— Eyton, Mon. Anat. 1838, 171. 

 -Inas jamaicctisis , "Lath." — Ord, cd. Wilson, VIII, 1825, 138. 

 Sp. Ch. — Bill grayish blue. Top of head and nape black. Sides of head below the eyes, with the chin, pure opaque white. 

 Lower part of neck all round, and the entire upper parts, with upper portion of sides, chestnut red. Under parts irenerally 

 lustrous grayish white, with an occasional brownish tinge ; crissuin pure white ; wings brown, without speculum, finely and 

 almost inappreciably sprinkled with gray ; tail nearly black. 



Female with the entire upper parts dark brown ; the back and wing coverts finely sprinkled with grayish. The under parts 

 brownish white, tinged with greenish brown across the lower part of neck. The brown of the head comes down below the 

 level of the eye, and there is an obscure dusky stripe parallel with its lower outline, from the commissure. 

 Length, 16.00 ; wing, 5.80 ; tarsus, 1.26 ; commissure, 1.80. 

 Flab. — Whole of North America. Abundant throughout the interior. 



The continuity of the white of the under parts is interrupted by the occasional appearance 

 of the basal brown of the feathers, owing to the shortness of the white tip, which thus gives rise 

 to the appearance of dusky transverse bands. 



