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Show 1879.] TRACHEA OF T H E GALLIN.E. 377 lateral portion of the atrophied ring. The first and second bronchial semirings are upturned laterally, and more slender than those below them. The first anteriorly sends upwards and inwards a lengthy process of about three times the thickness of the body of the ring itself, cut away obliquely, so that its upper end looks inwards and a little upwards, nearly to meet its fellow, from which it is separated by a narrow triangular fibro-cartilage, developed at its base from the middle of the anteroinferior margin of the penultimate ring of the trachea. The second semiring is slightly swollen at its ends to articulate with the semiring above. The interval between the penultimate ring and the first semiring is necessarily considerable, and is quadrate as well as slightly biconcave ; that between the first and second semiring is meniscoid, convex upwards, and shallow. The bronchial semirings below the second are peculiarly lengthy, especially the fifth, and pointed at the ends. Strangely, also semiring three, a short distance external to its anterior termination, articulates by small special facets with those above and below. The bronehidesmus is particularly strong. B y Temminck1 this windpipe is imperfectly figured. Gallus bankiva at first sight seems to have the lower end of its windpipe constructed upon quite a different type from that of any of its allies, although I have reason to believe that other species fill up the gaps between it and other Phasianidae. The lower extremity of the trachea is very much compressed from side to side, whilst it is correspondingly augmented in depth from before backwards. The antero-posteriorly directed pessulus joins in front the base of a considerable median triangular cartilage, which, with upward-directed small-angled apex, reaches as high as the level of the antepenultimate tracheal ring ; posteriorly it joins a similar but smaller cartilage, the apex of which does not quite reach the penultimate ring. With the lateral angles of these triangular cartilages, the anterior and posterior extremities of the first bronchial semirings freely articulate. These semirings are large and much curved, with the convexity directed downwards. Anteriorly they meet, but do not articulate with the scarcely modified second semirings, from which they are quite independent behind. The last tracheal ring is thin and band-like, joining the lower ends of the sides of the anterior triangular cartilage in front, whilst behind its free extremities are separated by a considerable interval, partly occupied by the posterior triangle. The penultimate ring persists as two straight lateral band-like rudiments fixed in the tracheal membrane, and nearly reaching both the anterior and posterior triangular cartilages. The antepenultimate ring is still further modified in the same direction, only the antero-lateral parts persisting as rudiments, not seen, therefore, in the back view of the organ. A short distance above the level of the apex of the anterior triangular cartilage, and some way below the first fairly normal tracheal ring, is a continuous filamentous transverse cartilage, with little extra pieces connected to it-incomplete in the middle line 1 Loc. cit. pi. iii. fig. 8. |