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Show 316 MESSRS. B. C A. WINDLE AND E. G. PARSONS ON [Mar. 7, Panniculus.-Bradypodidce. The three records which we have of this muscle in Bradypus all agree in stating that the dorsal portion is very feebly marked. The ventral part or abdomino-humeralis passes -backwards as far as the outer surface of the thigh, whilst anteriorly it covers in the axilla, and is attached to the pectoral ridge deep to the pectoral muscle. W e have succeeded in satisfying ourselves that the sterno-facialis and sphincter colli are both absent in this family. Myrmecophagidce. In Cycloihurus the alidomino-humeralis resembles that of the Bradypodidce; it is well marked on the outer side of the thigh and extends as far as the knee. Humphry (17) describes a femoral attachment between the ectogluteus and vastus externus. In Tamandua (14) the dorso-humeralis is better developed than the abdomino-humeralis. Dasypodidce. In this family the panniculus is remarkably specialized, being divided into a number of slips which are inserted into the carapace. In Tatusia peba (25), Macalister describes seven parts, viz.: (a) abdomino-femoral, from the mid-line of the abdomen to the anterior edge of the femur; (b) abdomhio-tergal, from the anterior part of the mid-line of the abdomen to the deep surface of the dorsal shield; (c) ischio-tergal, from the tuber ischii to the deep surface of the pelvic shield; (d) pectoro-brachial, from the mid-line of the pectoral region to the fascia on the inner border of the arm ; (e) dorso-pectoral, from the integument over the clavicular pectoral to the anterior angle of the dorsal shield ; (f) from the angle of the mouth and the skin over the side of the jaw to the lateral border of the dorsal shield as far as the elbow ; (g) a similar and longer slip connected with the posterior trapezius. In Dasypus villosus (22) the most important bundle, which is probably platysmal in its nature, passes from the lower part of the zygoma to the cephalic border of the first part of the dorsal carapace and thence backwards as far as the fourth segment. Another band passes from the skull above the orbit to the head-shield. In Dasypus sexcinctus (24), Cuvier and Laurillard figure these zygomatic and occipital bundles, the former being, as in villosus, much the larger of the two. The acromio-basilar of Galton (23) is well-marked and passes from the skull anterior and lateral to the occipital slip to the acromion process at its junction with the spine. It lies wholly superficial to the trapezius, and is clearly the same as Cuvier's portion cervicale du trapeze. In Ghlamydophorus (27) there is no connection between the panniculus and the sphreronia; the abdomino-humeralis is represented by a thin slip from the external aspect of the thigh to the surface of the abdomen. Some fibres, Avhich appear to be quite separate from those of the trapezius, pass from over the scapula to the cephalic shield, and these may probably be homologous Avith the acromio-basilar of Dasypus. In the Manidce the panniculus more closely resembles the more common mammalian arrangement. The abdomino-humeralis is Arery thick and dorsally inseparable from the dorso-humeralis, the two covering the outer side and |