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Show 714 ON THE ANATOMY OF TETROGALE XANTHOPUS. [June 16 the two portions of gut are connected by a fold of peritoneum which reaches almost to the extremity of the caecum. Tlie Genito-urinary System. The male genito-urinary organs answered so well to Owen's description that I refrain from making any remarks about thern. The Respiratory System. The Larynx is remarkable for the great size of the arytenoids which, as Owen points out1, are situated at tbe side instead of on the dorsal surface. The part of these cartilages which points towards the head of the animal is a broad convex border instead of forming tbe apex of a pyramid; from the anterior end of this border the short vocal cords pass to the thyroid. There are no false vocal cords or ventricles. The epiglottis is large, and is deeply notched in the middle of its free edge. The ventral part of the anterior edge of the thyroid cartilage curls over towards the cavity of the larynx and forms a little pouch just behind the stalk of the epiglottis. • The Trachea is a little over 4 inches long; the cartilaginous rings form rather more than complete circles, so that one end overlaps the other on the dorsum : this arrangement allows a considerable dilatation of the tube. The Thyroid Gland is described in the account of the vascular system. The Lungs are remarkable, as is usual in Kangaroos, for the small amount of lobulation which they exhibit. The right lung is much larger than the left and has a well-marked azygos lobe; from the ventral border of this lung a long triangular process projects, in front of which are two notches. The left lung bas one notch on its ventral border, but, like the right, is undivided by fissures. Owen 2 states that in Macropus major the right lung has two notches in its anterior (ventral) border, while the left is undivided; in M.parryl both have one or two notches ; in another Kangaroo he found the right lung divided into four lobes and the left into two. On neither side is there any eparterial bronchus. 1 'Anatomy of Vertebrates,' vol. iii. p. 584. - ' Anatomy of Vertebrates,' vol. iii. p. 577. |
