376 DB. B. C. A. WINDLE AXD ME,. F. G. PARSONS OS THE [Apr. 6, 



and in the greater differentiation of the muscular planes giving 

 an increased power of expression. In C. vulpes (43), Dieck 

 (XXXA^III.) 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 Canidfe more than the 

 Felidas, especially in the lesser development of the sphincter colli. 

 In Nasua (60) there is a strong levator alse 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 Cams (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, Touug (12) states that 

 the temporal is with difficulty separable from the masseter. 

 Watson (XV.) and Touug (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 w-hole 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 thestylo-mandibular ligament. 



Diyastric. — This, in spite of its name, is really a monogastric 

 muscle in the Carnivora j it is thick and strong and rises from the 



