Of another male, length to end of tail 19 1/2, to end of claws 21 1/2, to end of wings 17; extent of wings 31.
Adult Female. Plate CCCXLII. Fig. 2.
The female is much smaller. Bill dusky, a portion at the end, not however including the unguis, dull yellowish-orange. Eyes and feet as in the male. Head and upper part of neck dull reddish-brown. Lower part of neck and the sides of the body brownish-grey, the feathers margined with pale grey. Upper parts greyish-brown, much darker behind; tail brownish-grey; wings brownish-black, seven of their coverts, excepting at the bases, white, the smaller coverts lighter and tipped with greyish-white; the legs and sides of the rump greyish-brown.
Length to end of tail 16 inches, to end of wings 15, to end of claws 17 1/4; extent of wings 28; wing from flexure 8 1/2; tail 3 1/4; bill along the ridge 1 3/8, from the angles 1 3/4, along the lower mandible 1 5 1/2/8; tarsus 1 3 1/2/8; hind toe 5/8, its claw 1 1/2/8; middle toe 2 2 1/2/8, its claw 3/8; outer toe 1/8 longer; inner toe and claw 2. Weight 1 3/4 lb.
An adult male examined. The tongue is 2 inches long, fleshy, papillate at the base, with two series of lateral filaments, a deep median groove, and a thin semicircular tip, as in many other ducks. The œsophagus is 10 inches long, of moderate diameter, dilated towards the lower part of the neck to 1/2 inch; its walls very thick; the proventriculus with numerous oblong glandules. The stomach is a large and powerful gizzard, of a roundish form, 2 inches long, and of equal diameter, its lateral muscles very large, and upwards of half an inch thick; its epithelium rugous. The intestine is 6 feet 1 inch long, its diameter varying from 5 twelfths to 4 twelfths; the rectum 4 inches long; the cœca 3 1/4 inches in length, their greatest diameter 2 1/2 twelfths. The contents of the stomach a soft mass of a reddish colour, in which are distinguished small mussels and remains of fishes, with some vegetable fibres.
The trachea is 9 inches long, for 4 inches narrow, its diameter being about 4 1/2 twelfths, and its rings, which are 60 in number, cartilaginous; it then forms an ovato-oblong expansion, which, when drawn out, is 2 1/2 inches long, and 1 inch in breadth, and is formed of ossified and flattened rings, narrower behind, placed obliquely, and about 30 in number; it then contracts to a diameter of 5 twelfths, and has 16 free rings, but below this the rings, 25 in number, become united or blended, and gradually expand into a vast irregular cavity, having a broad bony frame in front, membranous behind, and separating to the distance of 1 inch, the bronchi, which are large, the right one much larger and longer than the left, and composed of 20 rings, all of which are almost complete and cartilaginous, excepting the two upper. The rings of the left bronchus, also about 20, are more incomplete.
Now for conjectures. These enormous dilatations are intended for strengthening the voice. But the voice is not strong in this duck. Well, then, they are receptacles of air, to enable the bird to keep longer under water. But the bird does not keep longer under water than many other ducks, and besides, the female, which has no such dilatations, dives as well as the male.
One use at least is this. A comparison of the windpipe of an American Golden-eye, with those of two Scotch ones, shews that the so-called Clangula Americana, is in this respect precisely similar to the Clangula chrysophthalma. Their digestive organs are also the same; and American skins compared with European skins, exhibit no differences of the slightest importance. Some individuals, especially males, have much larger bills than others, but this happens in the birds of both countries, and the Golden-eye is not singular in this respect. Clangula Americana, therefore, requires a better elucidation than the appendage of a “Nob,” before it can be admitted as a species.
RUDDY DUCK.
Fuligula rubida, Bonap.
PLATE CCCXLIII. Male, Female, and Young.