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Show 1871. J MYOLOGY OF THE KINKAJOU. 549 by means of a thin aponeurotic expansion across the dorsal mesial line, having no spinal attachments. The object of this arrangement is no doubt to facilitate the rapid approximation of the scapulae, e. g. when the animal tears its prey. This muscle is inserted into the anterior three-fourths of the scapular spine. Besides there is an additional portion segmented from the preceding, which arises from the spines of the dorsal vertebrae from the second to the tenth inclusive. It crosses the inferior half of the vertebral border of the scapula and the adjacent portion of the infraspinatus, to be inserted into the lower and posterior half of the spine of the scapula. The serratus magnus and levator anguli scapulee constitute one large and continuous muscle. It arises, by fourteen digitations, from the transverse processes of the six lower cervical vertebra., and from the nine upper ribs. The digitations are arranged in a radiate manner, advancing towards the middle line from the first to the sixth ribs, and then recedes to the ninth. Those attached to the six upper ribs extend as far as the anterior extremities of the vertebral ribs, springing from their upper margins; the three succeeding digitations do not advance so far forwards, and fit into corresponding processes from the external oblique muscle of the abdomen. Between the digitations attached to the second and third and third and fourth ribs pass the two superior muscular slips of insertion of the scalenus posticus. The insertion of the serratus magnus does not present that twisted appearance common to the Primates; but it is simply flattened and extends the whole length of the vertebral border of the scapula. In the Paradoxurus there is a similar arrangement, except that the levator anguli scapulae representative is attached to all the cervical transverse processes; the upper and anterior one, no doubt, representing that which I have described in the Kinkajou as the levator scapulae minor. The pectoral muscles are three in number, viz. an anterior, a posterior superior, and a posterior inferior. The anterior of these three pectoral muscles corresponds to the pectoralis major. It is elongated and irregularly quadrilateral in shape, and entirely muscular. It is attached proximally to the anterior half of the sternum and to the sternal extremities of the second to the seventh ribs inclusive. The most anterior fibres overlap, and are closely associated with the fibres of origin of the sterno-mastoid muscle. It is attached by its distal fibres to the upper half of the anterior border of the shaft of the humerus, extending from the great tuberosity to the distal end of the delto-pectoral ridge. It is partly blended with the fibres of insertion of the levator humeri. The posterior superior muscle is situated behind the preceding. It is attached to the second, third, fourth, fifth, sixth, and seventh ribs close to the sternum, and also to the adjoining margin of the sternum. The muscular fibres converge as they pass outwards, finally terminating in a fascial expansion on the tuberosity of the |