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Show 94 MESSRS. WATSON AND YOUNG ON THE [Jam 14, Complexus tertius.-A series of strong fleshy bundles extends between the articular processes of the posterior cervical vertebrae ; continued forwards as a separate muscular band, the fibres pass to the transverse process of the atlas, forming the muscle so-named. Murie describes a similar structure in II. brunnea, and regards it as corresponding to the complexus tertius in Hyrax. The homological significance of this muscle appears, however, to have received varied interpretations by different anatomists, e.g. Mivart and Murie1, recording their observations on the Myology of Hyrax capensis, write that " Meckel describes it as the transver-salis cervicis; but this," they proceed to say, " it cannot be, as the transversalis cervicis is always the continuation into the neck of the longissimus dorsi, whereas our muscle lies distinctly internal to such continuation ;" they further state that the true transversalis cervicis is the cervicalis ascendens of Meckel. Whilst agreeing with the view of Mivart and Murie as to the nature of the muscle under consideration, and regarding it as a complexus tertius, we must take exception to their exposition of Meckel's views. W e do not believe that Meckel described the muscle under any name, certainly in no case as forming solely the transversalis cervicis; neither does he confound the cervicalis ascendens with the transversalis cervicis. The posterior recti and obliqui have their usual attachments. Obliqus inferior is comparatively very large. The rectus capitis posticus major consists of two parts, superficial and deep ; such is also the case in the Dog, Bear, and Civet. Rectus capitis lateralis is inseparable from the superior oblique. Spinalis colli extends from the first dorsal and last five cervical spines to the spine of the axis ; there is no semispinalis. The cervical intertransversales, arranged in pairs, are exceedingly large and strong. Muscles of the Back, Thorax, and Abdomen. The panniculus carnosus in H. crocuta, as in Carnivores generally, forms an extensive muscular sheet, specially strong on the lateral aspects of the trunk, and extending more or less over the dorsal and ventral regions. It arises from the fascia over the latissimus dorsi, and posteriorly from that covering the thigh. There is, however, no femoral attachment. The fibres converge towards the axilla and join the latissimus about four inches above its humeral attachment. Trapezius is small. It arises from the spines of the seven anterior dorsal vertebrae and from the ligamentum nuchae opposite the last two cervical spines. Its insertion is into the whole length of the scapula. This represents the posterior part of the trapezius of Meckel in H. striata, his anterior portion being our levator humeri. The latissimus dorsi takes origin from the posterior eleven dorsal spines and from the lumbar aponeurosis; it has no costal attachment. Joined by the panniculus, it is inserted along with the teres 1 " On the Myology of Hyrax capensis," P. Z. S. 1865, p. 333. |