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Show 1879.] ANATOMY OF HY^NA CROCUTA. 93 The mylo-hyoid extends from the inner surface of the mandible (where its attachment reaches from the anterior margin of the ramus to about two inches from the symphysis) to the hyoid bone posteriorly, and in front of this to a median raphe common to it and its fellow. Genio-hyoid and genio-hyoglossus muscles, arising from the symphysis of the lower jaw, have their usual insertions. The hyoglossus is also normal in its connexions. Styloglossus, usually strong in Carnivores, is in H. crocuta very large. It arises from the cranial end of the stylo-hyal bone, and passes to the side of the tongue. Wide in the Civet, it arises from the middle of the stylo-hyal. The stylo-pharyngeus, also very strong, is from the stylo-hyal and tympano-hyal bones. There is no stylo-hyoid. Meckel states that this muscle, which is ordinarily wanting in Carnivores, is present in H. striata, Cat, Dog, and Genet; Macalister found it in the Civet. Scaleni.-Of these there are but two, both of which are situated behind (dorsad) the brachial plexus ; consequently the scalenus an-ticus must be regarded as wanting. The scalenus medius passes from the transverse processes of the fifth, sixth, and seventh cervical vertebrae to the first rib. S. posticus is from the fifth cervical vertebra to the fourth and fifth ribs. The scalene muscles in H. crocuta are therefore similar in arrangement to those of II. striata and Dog, as described by Meckel. Douglas, however, avers the existence of three scalenes in the latter animal, thus agreeing with H. brunnea, in which, according to Murie, a s. aniicus exists along with the medius and posticus ; such is also the condition which obtains in the Civet. The rectus capitis anticus major, from the transverse processes of the second to the sixth cervical vertebrae, to the basiocciput is but indistinctly separated from the rectus capitis anticus minor. The latter muscle springs from the arch of the atlas, and lies under cover of the major. Longus colli occupies the cervical and anterior dorsal regions. Its fibres extend between the transverse processes and bodies of the various vertebrae over which it passes, with the exception of the axis, and terminate anteriorly at the arch of the atlas. These muscles do not differ materially in the Carnivora. Splenius arises from the whole length of middle line of the neck, first two dorsal spines, articular processes of last five cervical and first dorsal vertebrae ; it has its insertion solely into the outer half of the transverse ridge of the occiput. There is therefore no splenius colli present. This condition is usual in Carnivores. Douglas, however, notes a cervical attachment of splenius in the Dog. Complexus.-This muscle forms an enormous fleshy mass in the region of the neck. It arises from the last five cervical articular processes and from the anterior two dorsal spines. Insertion is into occiput beneath splenius. There is no division into complexus and digastric, such as Meckel notes in H. striata. |