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Show 858 MR. ST. GEORGE MIVART ON THE [Dec. 6, portion of the lower part of the longissimus dorsi. Diverging outward it is implanted into the postero-internal aspect of the suspensorium, and into the back of the skull. At its insertion this muscle has the postero-superior part of the temporal at its inner side, and the upper part of the depressor mandibulse at its outer side. It is also implanted above and internal to the attachment of the sterno-mastoid. Sacro-lumbalis (fig. 2, S). This muscle arises from the dense fibrous tissue in which the ilium is more or less imbedded. Thence its fibres pass forward, being conterminous below with the origin of the external oblique, and conterminous above with the inferior margin of the lower part of the longissimus dorsi. Anteriorly this muscle becomes very indistinct, being with difficulty separable from the similarly directed fibres of the external intercostals. Passing forward beneath the latissimus dorsi, the trapezius, and the levator claviculse, it ends by constituting the muscle next described. Cervicalis ascendens (fig. 7, C. A). This is the continuation forward of the sacro-lumbalis. It is connected with the ribs and transverse processes of the more anterior vertebrae, and is inserted into the atlas. Scalenus (figs. 5 and 7, Sc). This lies immediately on the ventral side of the cervicalis ascendens. It arises from the side of the atlas, and, passing backward between the complexus minor and rectus anticus, is inserted into the first rib which is elongated but does not reach the sternum. The sterno-mastoid * (fig. 5, S. M, and figs. 6 and 7, St. M) is short, and is directed strongly upward as well as forward. It arises from the antero-external part of the coracoid groove of the sternum, and is inserted into the postero-internal aspect of the suspensorium. It is in close proximity to the sterno-thyroid; but the narrow omohyoid passes between. External oblique-\ (figs. 1, 4, 5, 6, and 7, E. O). This muscle is not largely developed. It arises by delicate fascia from the outside ot the ribs (beginning with the first elongated one), at the line of fascia which bounds infero-externally the sacro-lumbalis. Anteriorly the origin of the muscle is less than half an inch above the angles of the ribs ; posteriorly it is more than half an inch above them. The muscular fibres do not nearly reach the inferior middle line ot the body, but end in a delicate aponeurosis. Posteriorly this muscle ends in a well-marked border (concave backwards), thus allowing the tendon of origin of the internal oblique to come into view behind and within it. The converging fibres in part unite with the rectus, and in part are inserted into the fascia binding down the muscles of the thigh. Anteriorly the external oblique is overlapped by the latissimus dorsi above, and is somewhat blended with the pectoralis below. * Meckel, I. c p. 282. t Meckel (/. c. p. 287) says the abdominal muscles of the Chameleon are exceptionally feeble and simple. They are so; but in C. parsmiii they are more developed (relatively as well as absolutely) than in the common Chameleon. |