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Show Is-' DR. .1. MUIUK ON SAIGA TARTARICA. [June !), vessels, which give the whole quite a banded network character; whereas in the Saiga the fibres of the nasal muscles proper and bloodvessels are so minute as to have more of a glandular aspect. In the Pachyderms the proboscis is as much an organ of touch and prehension as of smell. In Saiga undoubtedly touch or the sense of feeling must be possessed to an unusual degree in this musculo-sensory nasal apparatus. The increase of powers of smell, however, seems to be its office ; for the Schneiderian membrane is that which most gains in superficial capacity, the power of retraction and movement, though ossessed by it, being secondary or adjunct. The distribution of .serves to the outside of this dilated nose-chamber is peculiar, inasmuch as the facial nerve (F.n.) is enormously developed. Piercing the parotid gland behind the ascending ramus of the mandible, it traverses, as in Sheep and Goats, superficially across the masseter to above the angle of the mouth, then, directed obliquely upwards and formards, splits into a vast number of thick branches. But the fan-shaped nervous plexus which spread over the entire face are by no means so few or so small as in Ovidse, compared with which they are of gigantic proportions. While some proceed towards the upper lip, the greater number pass underneath the zygomatic and 1. 1. s. alaeque nasi muscles, and, piercing the deep nasal muscles, ramify finally on the fibrous wall of the nares, both laterally and in front. In fact they similate the nervous distribution on the Pig's mobile and sensory snout ; only in Saiga many more go to the lateral aspect of the nares, and comparatively fewer to the extremity of the nose. In most Bovines the infraorbital nerves are large relatively to the temporo-facial; but in S. tartarica the reverse obtains (fig. 8, /. o. n). This may be accounted for by the upper lip of the former requiring greater nervo-muscular power ; whereas in the latter, as has been shown, the nose acquires prominence, being the active sensory and mobile organ. Among cranio-facial muscles other than those mentioned, the temporalis (Te), as in Ruminants generally, has a small superficial area. The masseter is double ; its superficial layer (Max), broad and thick, arises by a strong tendon from the maxillary prominence, and by fibres from the lower edge of the orbit; posteriorly and below it has a wide insertion into the angle of the mandible. The second, deeper layer (Ma2) has more vertically directed fibres; they arise from the anterior half of the zygomatic arch and lower surface of the orbit, and are inserted into the anterior half of the ascending mandibular ramus. The buccinator is moderately thick, elongated, and narrowed behind. The inferior labial group of muscles are but moderate in size. The sterno-mastoid, as Owen remarks in the Giraffe, is according to attachment a sterno-maxillaris, each belly posteriorly being in close union with the sterno-hyoidei, and anteriorly ending by a strong tendon, which amalgamates with that of the masseter primus, they together being firmly fixed to the maxillary eminence. This facial |