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Show 514 MR. A. H. GARROD ON THE ANATOMY [June 6, length ; and the muscles of the thigh are similarly arranged to those of most Passeres, the myological formula * being A,XY, the ambiens muscle being absent, at the same time that the flexor longus hallucis is quite independent of the flexor digitorum perforans. The palate is beautifully figured by Mr. Parker in his memoir on iEgithognathous birds f; and I take this opportunity of giving a view of the back of the skull and of the sternum, which present features of interest. It will be noticed that the temporal fossae extend across the occipital region of the skull, and nearly meet in the middle line behind; this condition, though frequently found in other families, is not one possessed by any Passerine birds except Pitta, as far as I am aware. Plate LIII. fig. 8 shows the sternum of P. cyanura ; in it the sternal notches are particularly deep. Menura superba is another bird in which our knowledge of the structure of the syrinx is very deficient. Mr. Eyton has described it J; but his account will bear supplementing. He tells us that "in addition to the usual sterno-tracheal muscles this curious bird has two other pair, both of which have their origin on the rings of the trachea on each side, at the point where it enters the cavity of the thorax. The anterior pair is inserted on the knobs at the extremities of the fourth bones of the bronchiae; the posterior pair are also inserted on the bronchiae, but on the three uppermost rings and on the posterior extremity of the fifth." Several opportunities having occurred to m e (partly through the kindness of Professor Flower in allowing me to dissect a specimen beautifully preserved in the Royal College of Surgeons, partly through the assistance of Mr. Edward Gerrard, and partly from my prosectorial advantages) of dissecting the syrinx of Menura superba, I take the present opportunity of describing it in detail and figuring it. In Menura superba the last sixteen rings of the trachea are peculiarly narrow from above downwards. These are carinate in front; in other words, instead of being flattened from without in wards (as is usually the case, and is so in the rings above the sixteenth in this bird), they are compressed from above downwards, by which means a sharp-edged ridge is developed, which projects outwards a short way beyond the level of the interannular membrane. The lowest of these rings, the last tracheal, whilst participating in this peculiarity, is modified to form the three-way piece, whence start the bronchi, an antero-posterior bar joining the downward-directed angles which are developed on the middle of the front and back of the ring, and supporting the syringeal semilunar membrane. As in the typical Oscines, the first three bronchial semirings participate in the formation of the syrinx, and are modified accordingly, being stronger, deeper, more flattened, and more approximate than those which follow. The first of these is simple ; the second is peculiar in being hollow and thin-walled, broader in front than behind, and broadest a short distance (about equal to its depth at the * Vide P. Z. S. 1874, p. 111. t Trans. Z. S. vol. ix. pl. lvi. fig. | Ann. & Mag. Nat. Hist. 1811, vol. vii. p. 49. |