GREAT AUK, _Nuttall_, Manual, vol. ii. p. 553. Adult in Summer. Plate CCCXLI. Figs. 1, 2. Bill as long as the head, feathered as far as the nostrils, beyond which it is very high, exceedingly compressed, tapering, and slightly declinate. Upper mandible with the dorsal line straight for an inch and a quarter, then declinate and decurvate to the end, the ridge very narrow, broader at the base; the sides nearly flat, with a basal ridge succeeded by a deep groove, then a large flat space, succeeded by eight oblique curved ridges, the edges sharp toward the end, the tip decurved and obtuse. Nostrils marginal, linear, short, pervious, but concealed by the feathers. Lower mandible with the angle long, the sides extremely narrow and linear for half their length, the horny part not being extended over the bone, which is covered with feathers, afterwards deep and compressed, with the dorsal line at first convex, then ascending and concave to the end, the sides flat, with about ten transverse ridges, the edges sharp, the tip deflected. Head large, oblong, anteriorly narrowed. Eyes rather small. Neck short and thick. Body compact and full. Wings extremely small, but perfectly formed. Feet placed far behind, short, very strong; tarsus short, compressed, anteriorly scutellate, laterally covered with angular scales, those on the hind part very small. Hind toe wanting; third toe longest, outer nearly as long, inner much shorter, lateral toes marginate, all with numerous scutella and several rows of angular scales above, and connected by reticulated webs. Claws rather small, narrow, arched, convex above, and obtuse. Plumage close, blended, very soft, on the head and neck short and velvety. Wings diminutive, much pointed; the primaries tapering to an acute point, the first longest, the rest rapidly graduated, their coverts long; secondaries short and broad, scarcely longer than their coverts. Tail short, pointed, of _fourteen_ feathers. Bill black, with the grooves between the transverse ridges white. Iris hazel. Feet and claws black. Fore part of the neck below, and all the lower parts white, of which colour also is a large oblong patch before each eye, and the tips of the secondary quills; the rest black, the throat and sides of the neck tinged with chocolate-brown, the wings with greyish-brown, the head, hind neck, and back glossed with olive-green. Length to end of tail 29 inches, to end of wings 23-3/4, to end of claws 31-1/2, to carpal joint 18-1/2; extent of wings 27-1/4; wing from flexure 7-1/8; tail 2-7/8, bill along the ridge 3-5/8, along the edge of lower mandible 4-1/2, greatest depth of upper mandible 1, depth of lower 5/8; width of gape 1-7/8; tarsus 2; middle toe 2-5/8, its claw 5/8; outer toe 2-5/8; its claw (3-1/2)/8; inner toe 2-(1/2)/8, its claw (4-1/2)/8. GOLDEN-EYE DUCK. _FULIGULA CLANGULA_, BONAP. PLATE CCCXLII. MALE AND FEMALE.