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Show 1871.] MYOLOGY OF THE KINKAJOU. 555 Paradoxurus and Caracal the two latter muscles are blended together ; the common tendon resulting from the combined muscle divides behind the extensor ossis metacarpi poliicis into two, to be inserted into the radial sides of the second and third metacarpals. The Kinkajou has these muscles much better developed and more perfect than the Paradoxurus and Caracal, and more in accordance with that condition which is called the average one in the human subject. This is not exactly true, however; for while the Kinkajou's muscles illustrate a decided advance above that of the Caracal, Paradoxurus, Dog, and Cat, and simulates the corresponding muscles in the Primates, still the human subject leads, and exhibits in the complexity of arrangement occasionally found in these muscles a tendency towards a further grade of muscular development which is minus a homologue in any other living animal. Douglas, in his 'Myographia Comparata,' states that the supinator longus is wanting in the Dog : I can scarcely say that it is wanting; it is aborted; its muscular belly is decidedly present and joined with the extensor carpi radialis communis. In several specimens which I have carefully examined, I have detected indications of segmentation of the supinator longus from its companion muscle. This was especially marked in a thoroughbred Spaniel which I had the pleasure of dissecting during last winter. The extensores communis digitorum and carpi ulnaris and the supinator brevis present the usual arrangement. The extensor minimi digiti divides into three tendons, to be distributed to the third, fourth, and fifth toes, joining the tendons of the common extensor on their ulnar sides. The extensor ossis metacarpi poliicis is a large fleshy muscle ; it is inserted into the trapezium and pollex metacarpal base. The extensor indicis divides into two tendons: the radial one is distributed to the pollex, and constitutes its only phalangeal extensor; the ulnar one joins the ulnar side of the common extensor tendon to the second digit, to be inserted along with it. Muscles of the Hind Limb. The psoas parvus arises fleshy from the front and sides of the three upper lumbar vertebrae, and from the disks between the first and second, and second and third. The tendon of insertion is broad and flat, and commences on the superficial aspect of tbe upper part of the muscle, the muscular fibres being prolonged upon the under surface of the tendon for nearly half its length. It is inserted into the ilio-pectineal eminence and brim of pelvis immediately posterior to the origin of the pectineus. It lies superficial to the quadratus lumborum and psoas magnus, simply separated from the latter by areolar tissue. The ilio-psoas. The psoas magnus arises from the front and sides of the bodies of the three tower lumbar vertebrae and their disks by fleshy fibres, and from the sacral surface and the posterior half of the pubic border of the ilium, where it becomes continuous with the iliacus. The latter arises from the iliac surface of the bone as a |