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Show 420 MR. A. SANDERS ON THE [June 9, vertebra, and from the furrow between the zygapophyses and transverse processes of the two following vertebrae. It is inserted into the lower border and external end of the exoccipital. Cervicalis ascendens is the continuation forward of the sacro-lum-balis. It also arises from the surface of the second and third cervical ribs, and is inserted into the transverse process of the first cervical vertebra and basioccipital above the insertion of the longus colli. Sacro-lumbalis arises from the posterior extremity of the ilium, and is attached to all the ribs between the points corresponding to the angles and the insertion of the longissimus dorsi. Longissimus dorsi begins at the transverse process of the fifth caudal vertebra, interdigitating with the first caudal muscle; it has an attachment to the posterior end of the ilium, and is inserted into the bases of all the ribs between the last muscle and the zygapophyses of the vertebras as far forward as the fourth cervical. Spinalis dorsi commences between the inner point of the first caudal muscle and the neural spine of the fifth caudal vertebra, and is inserted into the neural spines of all the vertebrae as far as the fourth cervical, occupying the space between the neural spines and the zygapophyses ; a small slip is continued forward beyond the fourth cervical, attached to the neurapophyses of the three anterior cervical vertebrae. Rectus posticus arises from the neural spines of the second, third, and fourth cervical vertebrae ; it is directed outwards, and is inserted into the upper and inner surface of the exoccipital, within and above the trachelo-mastoid. Rectus anticus major arises from the point of the external apophysis of the basioccipital, and is inserted into the hypapophysis and side of centrum of the first cervical vertebra, and in the same way into the rest as far as the sixth, and into the side of the centrum of the seventh. Scalenus arises from the side of the centrum of the second cervical vertebra dorsad of the last muscle, and is inserted into the cervical ribs from the first to the fifth, enclosing them in a triangular muscular mass, also into the sides of the bodies of tbe vertebrae belonging to these ribs; behind it is continuous with the intercostals. Rectus abdominis arises behind from a tendinous arch extending from the hook-like process of the pubis in front of the femoro-pelvic articulation to the ischium, which might be called ischio-pubic ligament, and is inserted by meaus of a fibrous membrane into the posterior extremity of the xiphisternum, and into the cartilage of the sixth sternal rib. It has six tendinous intersections running transversely across its fibres and occupying the whole thickness of the muscle. A n offshoot is given off just beyond the most posterior intersection, which goes to be inserted into the hook-like process of the pubis; this appears to represent tbe pyramidalis. External oblique arises by fourteen digitations, each loosely attached to a rib at the external edge of the sacro-lumbalis ; the first digitation belongs to the seventh cervical vertebra, towards the middle line; it is inserted behind to the hook-like process of the |