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Show 550 MR. J. BESWICK-PERRIN ON THE [June 20, humerus, into which it is implanted. It also sends off a fascial process which blends partly with the capsular ligament of the shoulder-joint, reaching as far upwards and forwards as the rudimentary coracoid process. This muscle closely accords with the second pectoral of birds in attaining to the position of an elevator humeri. The posterior inferior muscle arises from the seventh, eighth, ninth, and tenth ribs, from the lower third of the mesosternum, and slightly from the xiphisternum. Its upper part is overlapped by the preceding muscles, while its tower portion appears on the same plane as the anterior pectoral. Its fibres are directed obliquely forwards and outwards, to be inserted into the middle of the inner margin of the delto-pectoral ridge. This muscle is joined at its insertion by a very large Achselbogen from the latissimus dorsi. In the Paradoxurus typus and Caracal there is a similar arrangement of the pectoral muscles, except that the posterior inferior portion in the latter animal has a much more extended attachment to the radial border of the humerus by means of an aponeurotic tendon. The epigastric muscle consists of two or three isolated bands of the panniculus carnosus, which spring from the antero-lateral aspect of the thoracic subtegumental fascia; these unite together at their anterior and outer extremity, forming a moderately strong muscle, which passes through the axillary cavity, joining the upper border of the Achselbogen close to its insertion into the humerus. The epicostalis arises from the third, fourth, and fifth ribs, close to the sternum. It passes in a direction obliquely upwards, forwards, and outwards, crossing superficial to the rectus abdominis muscle (which is prolonged as far forwards as the second and first ribs). It is inserted into the first rib directly in front of the outer half of the preceding muscle. This muscle has a similar arrangement in the Paradoxurus typus and Caracal. The subscapularis in neither of these animals presented any notable peculiarities. The latissimus dorsi, teres major, and the dorso-lateral panniculus constitute by their intimate distal association one large, extensive, and complex muscle. The latissimus dorsi occupies a central position between the three. The proximal attachments have the same disposition which is common to the majority of the higher animals. Distally, the latissimus dorsi divides into three portions-a superior, mesial, and inferior. The superior constitutes the Achselbogen of the German authors. It is inserted into the delto-pectoral ridge behind the pectoral muscles, as already mentioned. This muscle crosses in front of the axillary vessels and nerves (exactly as it does in the human subject when present), and is joined prior to its insertion by a contributory slip from the dorsal panniculus. The mesial portion blends with the teres major, the two being inserted together into a depression internal to the delto-pectoral ridge. The inferior portion is given off in conjunction with the preceding. It passes down the inner and posterior aspect of the arm as a strong wedge-shaped muscle, and is finally inserted into the anterior and |