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Show 376 DR. B. C A. WINDLE AND MR. F. G. PARSONS ON THE [Apr. 6, and in the greater differentiation of the muscular planes giving an increased power of expression. In C. vulpes (43), Dieck (XXXVIII.) describes almost as many muscles as in the human face, but speaking generally his description agrees with our own. The other families seem to resemble the Canidse more than the Felidae, especially in the lesser development of the sphincter colli. In Nasua (60) there is a strong levator alas nasi divided into two bundles, which give the great mobility to that creature's snout. Temporal.-The temporal muscle rises from the side of the skull as high as the sagittal crest when this is present and as far back as the occipital curved line. There is always a tendinous plane in the substance of the muscle which divides it into two fleshy layers and to which both these layers are attached. In Ictonyx (70) and Lutra (74) it was noticed that this plane was only present in the anterior part of the muscle. As a rule the muscles of opposite sides meet at the sagittal crest, but in Ictonyx (70) and Canis (31) they are separated by a slight interval, while in Lutra (74, 75), owing to the breadth of the skull, a considerable space divides them. In Viverra civetta, Young (12) states that the temporal is with difficulty separable from the masseter. Watson (XV.) and Young (XIV.) have drawn attention to the great development of the masticatory muscles in the Hyaenidas. Masseter.-This muscle is always very strong. It rises from the whole length of the zygomatic arch as well as from the deep surface of the temporal fascia above the arch. As a rule the muscle can easily be separated into a superficial and a deeper layer; the former of these rises from the outer surface of the malar bone and from the anterior half of the zygoma, its fibres run downward and backward to be inserted into the lower border of the mandible near the angular process, where they blend slightly with those of the internal pterygoid, they are also inserted into the lower part of the external surface of the ramus. The deep part rises from the whole length of the zygomatic arch, its fibres converging on to the upper part of the surface of the ramus of the mandible. In Procyon lotor (53) it was noticed that this deep part was again easily separable into two layers, superficial and deep, an arrangement which, however, we have not seen in any other animal. Buccinator.-This muscle is fairly well developed in all Carnivora, but shows nothing of special interest. It is attached to the alveolar margins of both jaws and blends anteriorly with the orbicularis oris. Pterygoids.-The external and internal pterygoids are with difficulty separable in Carnivora ; the former rises from the external surface of the palatine bone and is inserted into the upper part of the internal surface of the ramus of the mandible. The internal pterygoid rises below and internal to the last, and is inserted into the mandible near its angle and into the stylo-mandibular ligament. Digastric.-This, in spite of its name, is really a monogastric muscle in the Carnivora; it is thick and strong and rises from the |