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Show 1871.] MYOLOGY OF THE KINKAJOU. 553 and terminates in the profundus tendon opposite the same point, and situated between the tendons of insertion of the forementioned flanking muscles. The three superficial tendons pass beneath the anterior annular ligament, traverse the palmar aspect of the fore foot, and form the perforated tendons of the second, third, and fourth digits. The perforatus tendon of the fifth digit is formed by the flexor brevis minimi digiti, to be presently described. In the Paradoxurus there are two flanking slips only. The flexor minimi digiti longus gives an additional slip to the fourth digit, joining the flexor-perforatus tendon opposite the first phalanx. Hhe flexor profundus digitorum has the same origin as the flexor poliicis longus and profundus digitorum of the human subject combined. Immediately above the radio-ulnar carpal articulation this large and fleshy muscle terminates in a strong and flattened tendon, which divides, opposite the middle of the metacarpal shafts, into five tendons,-one, the smallest, to the pollex; the remainder to the respective digits, perforating the superficial flexor tendons. This muscle has associated with it four lumbricals, which are disposed as in the human subject. There is no representative of the coronoid origin of the flexor longus poliicis, so common in the human subject. The flexor minimi digiti longus. This peculiar muscle arises from the pisiform bone and from the tendon of the palmaris longus internus. Its muscular belly is wedge-shaped, and terminates in a long, slender tendon, which splits to allow the perforans tendon of the fifth digit to pass to the terminal phalanx. It is inserted into the sides of the base of the second phalanx of the fifth digit. I have found the homologue of this muscle several times in the human subject ; in one specimen it was especially remarkable, arising by two distinct heads-one from an aborted and entirely tendinous representative of an additional palmaris longus, the other from the tendon of the flexor carpi ulnaris. These two heads united together immediately above the wrist-joint to form one well-developed muscle, which finally joined to be inserted with the abductor minimi digiti. Professor W o o d has recorded several similar specimens* under the name of abductor minimi digiti. This muscle is not, however, an abductor, but decidedly a flexor of the little digit, and finds its homologue in the perforatus flexor of the fifth digit in the Carnivores. The abdador minimi digiti arises from the pisiform bone. It is inserted into the base of the first phalanx and the inner sesamoid bone opposite the metacarpo-phalangeal articulation. The flexor brevis minimi digiti brevis arises also from the pisiform bone and tendon of the flexor carpi ulnaris. It is inserted into the base of the first phalanx on its ulnar side, and into the sesamoid bone. Besides these muscles there is another one, which corresponds in position and attachment to the opponens. It arises tendinous from the unciform bone and from the tendon of the flexor carpi ulnaris, prolonged from the pisiform to the fourth metacarpal base; As it passes along the metacarpal bone it divides into two portions. They are inserted into their respective sesamoid bones at the base of * " Variations in H u m a n Myology," Royal Society's Proceedings, June 1868. |