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Show 1882.] MR. FORBES ON THE TRACHEA OF SELEUCIDES. 333 2. Note on a Peculiarity in the Trachea of the Twelve-wired Bird-of-Paradise (Seleucides nigra). By W . A. F O R B E S, B.A., Prosector to the Society. [Received March 7, 1882.] The death (from congestion of the lungs, with resulting haemorrhage, and thickening of the walls of the intrathoracic air-cells) on Feb. 22nd last of the male Seleucides nigra, purchased by the Society on March 19, 1881 l, has given m e the opportunity of observing a peculiarity in the construction of its trachea of a nature unlike any thing of the kind yet known to me. The windpipe, for the greater part of its course, has the normal avian structure, the tracheal rings, which are ossified and, as usual, notched both before and behind, being of the ordinary form, and separated by but narrow intervals from each other. For a space, however, of about 1 inch above the largely developed short pair of intrinsic muscles, the interval comprising 8 tracheal rings, it becomes peculiarly modified, the tube itself becoming slightly dilated and flattened antero-posteriorly, whilst the tracheal rings become broader, and ossified along the middle of their depth, the borders only remaining cartilaginous. This ossified part of each ring is slightly concave, so that when seen laterally the cartilaginous margins project slightly from it, the whole ring being thus like a fluted table-napkin ring, when seen in section. The intervals between these peculiar rings are very much deeper than those above, and occupied by delicate membrane only, so that all this part of the trachea is highly elastic. The sterno-tracheales are inserted just below the lowest of these peculiar rings, which is the last but three of those composing the trachea-the next two, which are very narrow, and the last, which is broad and bears the pessulus, being concealed from view by the largely developed syringeal muscles, of which there are four pairs, all, except the smali anterior long muscle, being inserted on the ends of the very strong third bronchial semirings. The lateral tracheal muscles are weak, extending, however, nearly to the thoracic end of the tube. Nothing like the modification of the trachea here described obtains in any other allied form of Paradise-bird that I have been able to examine (including Paradisea papuana and rubra, Ptilorhis alberti, Phonygama gouldi, Manucodia atra, Ptilorhynchus violaceus and smithi) ; nor do I know any structure in other birds quite comparable with that now described, which is probably correlated with the very loud harsh note of these birds2. In all other respects Seleucides is, as might have been expected, a typical oscine Passerine. 'See P. Z.S. 1881, p. 450. 3 Mr. Wallace, speaking of this species, says (Malay Archipelago, ii. p. 254, London, 1869):-"It has a loud shrill cry, to be heard a long way, consisting of cah, cah, repeated five or six times in a descending scale; and at the last note it generally flies away." |