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Show 164 DR. R. W. SHUFELDT ON [Apr. 1, pectoralis II. of Stannius, and the epicoraco-humeral of Mivart. Fiirbringer also called it the supracoracoideus. As in Liolepis, the supraspinatus is covered by the deltoideus at least for its inner anterior part and anterior border. Mr. Sanders, who says that he has "seen Prof. Rolleston's paper (Trans. Linn. Soc. vol. xxvi. pt. 3), ' On the Homologies of certain Muscles connected with the Shoulder-joint,' in which he goes far to prove that the ' epicoraco-humeralis' (which was Dr. Mivart's name for the supraspinatus) corresponds to the subclavius ; but these differences of interpretation are reconciled by Mr. Galton's paper ' O n the Myology of the Orycteropus capensis,' in the same volume, in which the author shows that the subclavius in that animal has, among other insertions, one into the fascia covering the supraspinatus. Another piece of evidence bears upon this point; I believe that the nerve which in anthropotomy supplies the supraspinatus, arises from the same cord of the brachial plexus and close to the same one which supplies the subclavius, so that the muscle in question really corresponds to the subclavius at its origin, and to the supraspinatus at its insertion" (P. Z. S. 1872). 22. The Infraspinatus in Heloderma is a broad, thin, and fan-shaped muscle which arises from a curved line occupying a middle position upon the external surface of the suprascapula. From this point of origin its fibres tend immediately to converge to a point, but terminate in a strong, flat tendon which inserts itself upon the tuberosity of the humerus just beyond the insertions of the deltoideus and supraspinatus. 23. The Teres minor Is one of the deeper muscles of this shoulder-girdle group, and it arises from the antero-external border of the coracoid and the adjacent margin of the scapula. Its fibres pass upwards, backwards, and outwards, when, becoming tendinous, the muscle inserts itself upon the proximal end of the humerus of the same side, just beyond its head. Not far from its insertion, the teres minor is bound down by a strong tendinous aponeurosis, which latter comes off from the tendon of the long head of the triceps, connecting this last with the head of the humerus. Fiirbringer called this muscle the scapulo-humeralis profundus, in which he was followed by Hoffmann ; and according to this latter author it represents the supraspinatus of Pfeiffer and Riidinger, the infraspinatus of Mivart, the suprascapularis of Rolleston, and the teres minor of Sanders: may we not in truth believe that there is still work to be done in the myology of reptiles ? 24. Serratus superficialis.-Two of the serrati muscles form an oblong fleshy mass upon the external aspect of the thoracic parietes, connecting the vertebro-costal ribs with the posterior border of the suprascapula. Serratus superficialis arises by two digitations, the most posterior of which springs from the outer surface of the posterior extremity of the second sternal rib, while the laro-er or anterior one comes off from a similar point upon the first sternal rib. Its fibres run forwards and upwards, and insert themselves upon the hinder border of the suprascapula, at its postero-inferior angle. |