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Show 1867.] DR. A. MACALISTER ON GLOBIOCEPHALUS SVINEVAL. 481 tendinous from the basilar process of the occipital hone, and ran backwards to be inserted into the posterior border of the thyroid cartilage, the thyro-hyoid membrane, and the posterior cornu of the hyoid bone. This muscle underlay the last named, with which it was partly continuous; it seemed to be an expanded representative of the cephalo-pharyngeus of Theile (figured as a human muscle in tbe Proc. R. I. A. vol. ix. pl. 6. f. 1 b). Relating to the actions of these muscles, there are many points very well worthy of note ; but I refrain from making any observations at present on the subject, as they will be detailed at length by Dr. Carte and myself on a future occasion in connexion with the anatomy of Balcenoptera rostrata. The muscles of the spine which remained in the specimen were :- 1. Depressor caudae. 2. A fragment of levator caudse. 3. A small part of latissimus dorsi; besides the following:-4. Scalenus anticus, from the first rib to the front of the transverse processes of the upper cervical vertebra. 5. Scalenus medius and posticus conjoined, from the first and second ribs to the upper cervical transverse and spinous processes; the portion attached to the latter was probably the germ of the serratus posticus superior, which otherwise was not visible. 6. Trachelo-mastoid, from the transverse process of the first cervical vertebra to the external side of the occipital bone at the junction of the exoccipital and paramastoid elements. 7. Rectus capitis posticus, from posterior part of the atlas to the hinder edge of the foramen magnum and occipital bone above that level. 8. Rectus capitis anticus, from the front of the bodies of the cervical vertebrae to the basilar process of the occipital bone. There were some points of interest in the dissection of the paddle or fore limb. On removing its thick greyish-black integument, all the bony elements of the typical anterior extremity were found in it, although some, as the carpus, metacarpus, and phalanges, were purely cartilaginous; consequently the exact number of the latter could not be distinctly reckoned. The dorso-scapular group of muscles had been removed before the subject was examined; but traces of a deltoid supraspinatus and infraspinatus existed, though there was no sign of a teres minor or teres major, which are present in Dolphins. The subscapularis, which was attached as usual to the subscapular fossa and inner side of the head of the humerus, was completely intersected by eight tendinous planes slightly radiating towards the posterior edge : this point is of interest, as in Balcenoptera rostrata there is hardly any sign of these intersections, otherwise so uniformly found in so many animals. This muscle does not pierce the capsule of the shoulder, nor is there a bursa beneath its tendon. The coraco-brachialis was short and fleshy, arising from the front of the coracoid process, whence it passed to be inserted into the capsule of the shoulder and into the front of the neck of the humerus. This corresponds to the short variety of this muscle described by many anatomists, noticed by Mr. Wood and others as an occasional occurrence in M a n (Journal of Anat. & Phys. vol. i. p. 47. f. 2). PROC. ZOOL. Soc-1867, No. XXXI. |