Bill greenish-black; iris as in the male; feet yellowish-orange, webs greyish-dusky, claws black. The general colour of the plumage is brownish-black; darker on the top of the head, the back, wings, and tail; on the breast and sides the feathers edged with dull greyish-white.
Length to end of tail 19 inches, to end of wings 15 3/4, to end of claws 18; extent of wings 31 1/2; wing from flexure 8 3/4; tarsus 1 5/8; middle toe 2 3/4, hind toe 9/12. Weight 2 lb. 2 oz.
In an adult Male, the tongue is 1 inch 9 twelfths long, has numerous conical papillæ at the base, is deeply grooved along the middle, has two lateral series of bristles, and terminates in a thin rounded lobe, 2 twelfths long. On the middle line of the upper mandible are about ten short conical papillæ, and on each of its margins about 35 lamellæ; on the lower an equal number. The heart is 1 inch 8 twelfths long, 1 inch 2 twelfths broad. The œsophagus, 8 1/2 inches long, is wide, its diameter at the upper part being 1 inch, towards the middle of the neck 1 inch and a quarter. The proventriculus is 1 1/2 inch long; its glandules cylindrical, 1 1/2 twelfths in length, and, as in all other ducks, arranged so as to form a complete belt. The stomach is a powerful gizzard of a roundish form, 1 inch 10 twelfths long, 1 inch 10 twelfths broad, its lateral muscles very large, the right 10 twelfths thick, the left 9 twelfths. In the stomach were various small bivalve shells and much gravel. The cuticular lining longitudinally rugous; the grinding plates 3/4 inch in diameter. The intestine, 5 feet 7 inches in length, has an average diameter of 6 twelfths. The rectum is 7 1/2 inches long, 8 twelfths in diameter. Of the cœca one is 3 inches 4 twelfths long, cylindrical, obtuse, 2 1/2 twelfths in diameter, the other 4 1/2 inches long.
The aperture of the glottis is 8 twelfths long, with numerous minute papillæ behind. The trachea presents the same structure as that of the Velvet Duck. Its upper rings, to the number of 9, are very narrow, and continuous with a large bony expansion, 7 twelfths long, and 8 twelfths broad. Beyond this part its diameter is 5 twelfths, gradually diminishes to 3 twelfths about the middle, then enlarges to 5 twelfths. In this part the number of rings is 78. Then comes a roundish or transversely elliptical enlargement, 1 inch 2 twelfths in breadth, 9 twelfths in length, convex before, slightly concave behind, and composed of about 12 united rings. The trachea then contracts to 4 twelfths and presently enlarges to form the inferior larynx, which is large, ossified, but symmetrical. In this space there are 6 distinct rings, and 10 united. The entire length of the trachea is 7 1/2 inches, its rings are all osseous and strong. The contractor muscles are very strong, pass along the sides of the lower dilatation, on which are given off the cleido-tracheals, then continue to the commencement of the inferior larynx, where the sterno-tracheals come off. The bronchial half-rings 25, unossified.
The cavity of the nose is very large, being 2 inches long, 1/2 inch in diameter at the lower part, continued narrow in front over the dilatation causing the external protuberance of the base of the bill. The olfactory nerves are of moderate size; the maxillary branches of the fifth pair very large.
AMERICAN AVOSET.
Recurvirostra Americana, Gmel.
PLATE CCCXVIII. Adult Male, and Young in Winter.
The fact of this curious bird’s breeding in the interior of our country accidentally became known to me in June 1814. I was at the time travelling on horseback from Henderson to Vincennes in the State of Indiana. As I approached a large shallow pond in the neighbourhood of the latter town, I was struck by the sight of several Avosets hovering over the margins and islets of the pond, and although it was late, and I was both fatigued and hungry, I could not resist the temptation of endeavouring to find the cause of their being so far from the sea. Leaving my horse at liberty, I walked toward the pond, when, on being at once assailed by four of the birds, I felt confident that they had nests, and that their mates were either sitting or tending their young. The pond, which was about two hundred yards in length, and half as wide, was surrounded by tall bulrushes extending to some distance from the margin. Near its centre were several islets, eight or ten yards in length, and disposed in a line. Having made my way through the rushes, I found the water only a few inches deep; but the mud reached above my knees, as I carefully advanced towards the nearest island. The four birds kept up a constant noise, remained on wing, and at times dived through the air until close to me, evincing their displeasure at my intrusion. My desire to shoot them however was restrained by my anxiety to study their habits as closely as possible; and as soon as I had searched the different inlets, and found three nests with eggs, and a female with her brood, I returned to my horse, and proceeded to Vincennes, about two miles distant. Next morning at sunrise I was snugly concealed amongst the rushes, with a fair view of the whole pond. In about an hour the male birds ceased to fly over me, and betook themselves to their ordinary occupations, when I noted the following particulars.
On alighting, whether on the water or on the ground, the American Avoset keeps its wings raised until it has fairly settled. If in the water, it stands a few minutes balancing its head and neck, somewhat in the manner of the Tell-tale Godwit. After this it stalks about searching for food, or runs after it, sometimes swimming for a yard or so while passing from one shallow to another, or wading up to its body, with the wings partially raised. Sometimes they would enter among the rushes, and disappear for several minutes. They kept apart, but crossed each other’s path in hundreds of ways, all perfectly silent, and without shewing the least symptom of enmity towards each other, although whenever a Sandpiper came near, they would instantly give chase to it. On several occasions, when I purposely sent forth a loud shrill whistle without stirring, they would suddenly cease from their rambling, raise up their body and neck, emit each two or three notes, and remain several minutes on the alert, after which they would fly to their nests, and then return. They search for food precisely in the manner of the Roseate Spoonbill, moving their heads to and fro sideways, while their bill is passing through the soft mud; and in many instances, when the water was deeper, they would immerse their whole head and a portion of the neck, as the Spoonbill and Red-breasted Snipe are wont to do. When, on the contrary, they pursued aquatic insects, such as swim on the surface, they ran after them, and on getting up to them, suddenly seized them by thrusting the lower mandible beneath them, while the other was raised a good way above the surface, much in the manner of the Black Shear-water, which however performs this act on wing. They were also expert at catching flying insects, after which they ran with partially expanded wings.
I watched them as they were thus engaged about an hour, when they all flew to the islets where the females were, emitting louder notes than usual. The different pairs seemed to congratulate each other, using various curious gestures; and presently those which had been sitting left the task to their mates and betook themselves to the water, when they washed, shook their wings and tail, as if either heated or tormented by insects, and then proceeded to search for food in the manner above described. Now, Reader, wait a few moments until I eat my humble breakfast.