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Show 814 MR. J. B. PERRIN ON BALAENOPTERA ROSTRATA. [Dec. 6, The teres major was not inseparably connected at its origin with the serratus magnus, but arose independently of it. It extended almost the whole length of the postaxial border of the scapula. The muscle, prior to its insertion, was joined along its upper border by a fascial process from the capsular ligament (ventral surface) (fig. 2, Pt). The teres minor was absent. The subscapularis (fig. 2, Sb. Sep.) presented more of the character of the muscle (described by Carte and Macalister) of the Globiocephalus svineval. It was very large, occupying the whole of the subscapular fossa. Its surface was traversed by seven tendinous intersections, which divided the muscle into eight nearly equal-sized fleshy slips. Its tendon of insertion was broad and moderately thick; its deeper portion was inserted into the neck of the ventral surface of the humerus, immediately below the head of that bone. Its superficial fibres were prolonged across the ventral surface of the humerus, forming a dense investment to it, on to the bones of the forearm, along which it was further continued, previously acting as the anterior connecting ligament, along with other tendinous expansions (viz. those of the pectoral and masto-humeral, which it joined), to the humero-cubital articulation. The coraco-brachialis (fig. 2, C.B.).-This muscle presented no differences in origin from that described by ("arte and Macalister. But its insertion differed materially from that found by them, both in the Baleenoptera and Globiocephalus. Its tendon of insertion, opposite the upper border of the distal attachment of the latissimus dorsi and teres major, divided into two tendons. The anterior tendon passed along the ventral aspect of the insertion of the latissimus as far as its lower border, where it terminated, being partly inserted into the humerus and partly joining the tendinous expansion of the masto-humeral. The posterior tendon passed behind the insertions of the latissimus dorsi and teres major, giving off a slip of attachment to the humerus immediately behind the upper part of tbe insertion of the latter muscle; the remainder of the tendon was prolonged downwards and backwards, spreading gradually out into an expansion three quarters of an inch wide, which joined the external head of the triceps to be inserted along with that muscle. The distal division of this muscle may be regarded as a tendency towards the formation of a second coraco-brachialis, as occasionally found in the human subject; and its passing behind the latissimus favours this view materially. Extensor communis digitorum (fig. 1, Ext. Com. Digti) arose, by a strong flat tendon, from the dorsal surface of the distal extremity of the humerus, immediately above the articulation. It passed down in the interval between the radius and ulna, lying in the interosseous space, in which situation it received additional fibres of attachment. It was crossed on its dorsal aspect by a strong fibrous band, and by its ventral aspect lay in contact with an imperfect interosseous membrane, thus being situated, as it were, in a membranous or apoueu-rotie tunnel. About three inches above the lower end of the radius |