One of the most remarkable deviations from ordinary forms in this bird is _the division of the trachea previous to its entering the thorax_. It may be described as very short, a little flattened, and quite membranous, the rings being cartilaginous and very thin. Its diameter at the top is 5 twelfths, and it is scarcely less at the lower part, where, half-way down the neck, is formed an inferior larynx, _k_, which is scarcely enlarged. The two bronchi _lm_, _l m_, are in consequence excessively elongated. They are compressed, 5 twelfths in diameter at the commencement, gradually contracting to 3 twelfths, and enlarging a little towards the end; and are singular in this respect that the rings of the upper fourth are incomplete, the tube being completed by membrane in the usual manner, whereas in the rest of their extent, the rings are elliptical, entire, stronger, and those at the lower part united or anchylosed on the inner side. The rings of the trachea are 105, of the two bronchi 73 and 71. The contractor muscles are feeble and terminate at the lower larynx; from which no muscle extends along the bronchi, which, until they enter the thorax, run parallel and in contact, being enclosed within a common sheath of dense cellular tissue. The bronchi have the last ring much enlarged, and open into a funnel, which passing backwards and terminating in one of the abdominal cells, is perforated above with eight or ten transverse elliptical slits, which open into similar tubes or tunnels, opening in the same manner into smaller tubes, and thus ramifying through the lungs. In the male bird, of which the upper part of the trachea has been destroyed, there are in one bronchus 80, in the other 71 rings, 20 of the upper rings being incomplete. The vertebræ of the neck have no resemblance to those of Herons, nor does that part curve in the same abrupt manner; and the sternum is in all essential respects similar to that of the Curlews, Tringas, and other birds of that family, it having a very prominent crest, with two deep posterior notches on each side. In fact, the sternum of Tringa Cinclus is almost an exact miniature of it. [Illustration] The compact form of the body, its great muscularity, the form of the legs, the length and slenderness of the neck, the form and bareness of the head, and the elongation of the bill, especially when it is laterally viewed, all indicate an affinity to the Tantali and Numenii. But the Spoonbills are also allied in various degrees to the Herons and Pelicaninæ; so that they clearly present one of those remarkable centres of radiation, demonstrative of the absurdity of quinary and circular arrangements, founded merely on a comparison of skins. RED-HEADED DUCK. _FULIGULA FERINA_, STEPHENS. PLATE CCCXXII. MALE AND FEMALE.