Adult Male in Spring. Plate CCXXXVI. Fig. 1.
Bill a little longer than the head, strong, straight, compressed, tapering. Upper mandible with the dorsal line slightly arched and declinate, the ridge broad and rather rounded at the base, narrowed towards the end, the sides sloping, the edges very sharp and inflected, obscurely serrated with minute oblique slits, and having a distinct notch close to the compressed, rather obtuse tip. Nasal groove wide at the base, extending narrow to near the tip; nostrils basal, linear, wider behind, longitudinal. Lower mandible with the angle very long and narrow, the dorsal line straight and sloping upwards, the sides flat, the sharp obscurely jagged edges slightly inflected, the tip very acute.
Head oblong, much compressed; eyes large. Neck long. Body rather slender, compressed. Feet rather long, robust; tibia bare at its lower part; tarsus covered anteriorly along its upper two-thirds with scutella, below and on the sides with large angular scales; toes long and rather slender, scutellate above, flat beneath, marginate; hind toe stout, fourth a little longer than second, third much longer; claws of moderate size, stout, arched, compressed, rather acute, that of middle toe beautifully pectinate on the inner edge.
Plumage soft, blended. Feathers of the upper and hind part of the head elongated and loose, with three very long, linear incurved occipital feathers, having their webs inflected. The feathers of the neck, especially of its lower part and sides, are also elongated, the latter curved backwards. Wings of moderate length, broad, rounded; primaries broad, rounded, the third longest, the first longer than the fourth. Tail short, slightly rounded, of twelve broad, rounded feathers.
Bill black. Bare loral space and eyelids yellowish-green; iris bright red. Feet yellow; claws brown. Feathers on the upper part of the head, the fore part of the back, and the scapulars, glossy blackish-green; anterior part of forehead white; neck anteriorly white, on the sides and behind shaded into pale lilac, the lower elongated feathers tinged with cream-colour; breast and abdomen white, similarly tinged. Wings, rump, and tail, light greyish-blue, tinged with lilac.
Length to end of tail 25 7/12 inches, to end of wings 25 10/12, to end of claws 30 4/12; extent of wings 44; wing from flexure 13 3/4; tail 5; bill along the ridge 3 2/12, along the edge of lower mandible 4 2/12; bare part of tibia 1 1/4; tarsus 3 1/4; middle toe 3, its claw 7 1/2/12. Weight 1 lb. 14 oz.
Young after first moult. Plate CCXXXVI. Fig. 2.
Bill and bare space about the eye yellowish-green, the ridge of the upper mandible, and part of the lower towards the end, black. Iris bright red. Feet pale greenish-yellow. At this period the occipital feathers are not developed. The general colour of the upper parts is light greyish-brown, the edges of the feathers paler; that of the lower parts dull white, tinged with grey and cream colour, with the central part of each feather greyish-brown; the feathers of the back and wings, as well as the secondary quills, have a long triangular spot of brownish-white at the end; the rump and tail more tinged with bluish-grey.
The Adult Female resembles the Male.