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Show 1899.] THE MYOLOGY OE THE EDENTATA. 317 front of the thigh and buttocks. Some fibres also find their way to the inner side of the thigh and there blend with the gracilis. Anteriorly the more ventral fibres, to which alone the name of abdomino-humeralis should be applied, pass deep to the pectoarls and are inserted partly into the ribs and partly into the pectoral ridge of the humerus. The more dorsal part of the pannicular sheet, or dorso-humeralis, is partly inserted with the abdomino-humeralis, deep to the pectorals, and partly runs to the fascia of the dorsal surface of the arm and the posterior border of the outer end of the spine of the scapula. In our specimens of Manis the platysma is quite rudimentary, though it appears to be Avell deAreloped in Manis javanica (34) (Macalister). In the Oryctero-podidce (35, 36) there seems to be a remarkably well-developed panniculus. W e have not, unfortunately, had the opportunity ourselves of dissecting the Aardvark, but the descriptions of the platysma in this animal which are at our disposal are quite clear, and seem to shoAv that it there reaches a development superior to anything which we have as yet met with in our researches into mammalian musculature. It is described as passing from the zygomatic region over the neck and shoulder and arm to the radial side of the forearm. Humphry (36) and Cuvier and Laurillard (37) both figure this extensive platysma, and both also figure a very well-marked sphincter colli or sterno-facialis running backwards to the hinder end of the sternum, superficial to the pectorals. Galton (35) describes a muscle running from the orbicularis oris to the hinder end of the thorax, where it is attached to the mid-line of the sternum : this, there can be little doubt, is the sterno-facialis (cf. " Lectures on the Muscles of Mammals," Journ. of Anat. & Phys. vol. xxxii. p. 430). The same author states that part of this muscle passes under the jaw and round the neck, a fasciculus Avhich quite clearly corresponds to the sphincter colli of other mammals. The abdomino-humeral part of the panniculus in this animal is also well developed (37). Facial Muscles. - There is little of special interest to note with regard to the facial muscles of the Edentates, and there is so much variety in the terminology employed by different writers that a satisfactory generalization is most difficult. All the animals seem to possess the orbiculares palpebrarum et oris, levator labii superioris, zygomaticus, depressor labii inferioris, and retractor naris, as well as anterior, superior, and posterior auricular muscles, the last-mentioned being usually the best developed of the three. The muscles of the face in Myrmecophaga have been described in great detail by Owen (Trans. Zool. Soc. vol. iv.). In Bradypus the zygomaticus is Avell marked, whilst the most remarkable feature in the Dasypodidce and Manidce is the great development of the retractor naris, which rises from the zygoma and passes directly forwards to the snout and is evidently a valuable adjunct in rooting and grubbing. Masseter.-In Bradypus (1) the muscle is bilaminar, but the two layers are not very easily separable. The superficial rises |