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Show 1899.] THE MYOLOGY OF THE EDENTATA. 319 delamination from the sterno-hyoid (M. jubata, Owen, XV.). In Tamandua and Cyclothurus it rises from the manubrium and is inserted into the mandible near the symphysis. In the Dasypodidce the sterno-maxillaris is also present in Dasypus (22), Tatusia (25), and Chlamydophorus (27, 28). In the Manidae no sterno-maxillaris was noticed nor is any recorded in Oryeteropus. The only animal iu which a tendinous intersection was noticed Avas Tamandua (14), in AAhich the condition existed in the sterno-maxillaris. Sterno-glossus.-This muscle has so far only been recorded in Myrmecophaga, Tamandua, and Manis. Whether it is present in Cyclothurus Ave are unable to state. It rises from the xiphi-sternum and the last one or two true ribs and passes forward at first deep to the sternum and costal cartilages, and is subsequently ensheathed, as has already been mentioned, in fibres derived from the mylo-hyoid, to be inserted into the tongue. In Myrmecophaga Owen points out that it is intersected in its thoracic portion by linese trans ver sae. Styloid Muscles.-The stylo-hyoid, glossus, and pharygneus seem to be generally present, and of these the stylo-glossus appears to be always the best developed. The stylo-pharyngeus is usually small, and the stylo-hyoid is sometimes absent. Omo-hyoid.-In no Edentate have Ave ever seen this muscle, nor is it specifically described by any author, though it is stated in one paper that Cuvier noted it in Myrmecophaga, a reference which we have been unable to trace. Stemo-cleido-mastoid.-In the Bradypodidce, Bradypus (1,3,4) is remarkable for having the two parts closely united, whilst iu Cholcepus they are distinct. In Bradypus the single muscle rises from the manubrium and the fascia external to it and may (3) get a slight origin from the rudimentary clavicle. It is inserted into the paramastoid aud paroccipital region of the skull and has the spinal accessory nerve on its deep surface. In Gholcepus both sterno- and cleido-mastoids are present, the latter coming from the middle third of the clavicle, and the spinal accessory nerve passes between them. The cleido-mastoid muscle Avhen it is present is, as in most mammals, inserted deep to the sterno-mastoid. In the Myrmecophagidce, Myrmecophaga and Tamandua have only a sterno-mastoid, but Cyclothurus, in Avhich the clavicle is well deAeloped, has both sterno- aud cleido-mastoids (17, 21). In one specimen of this animal (19) there are described distinct sterno-mastoid, cleido-occipital, and cleido-mastoid, the latter lying deep to the cleido-occipital. It is to be regretted that the relation of the spinal accessory nerve to these three muscles is not recorded. In the Dasypodidce, Dasypus (22, 23, 24), Tatusia (25, 26), and Chlamydophorus (27) have separate sterno- and cleido-mastoids. In the last-mentioned animal, Hyrtl (28) mentions that the sterno-mastoids of opposite sides are fused in the neck. In Manis (29) the cleido-mastoid is absent. In Oryeteropus (35, 36, 37) both sterno- and cleido-mastoids are |