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Show 354 DR. J. MURIE ON T H E [May 26, chiefly due to the depressed rearward angle at which the horns come off. Some fossil forms, however, more markedly agree with the Prongbuck in the above respect, the Antilope palceindica of Falconer to wit. The Deer, as a group, may be said to have a depressed skull; in such forms as the Reindeer and the Elk it is very obvious. The seeming affinity of the Prongbuck to the Giraffe, in their both being deprived of false hoofs, is dispelled, so far as contour of skull is concerned (the former being deficient in the median frontal protuberance so peculiar to the latter), as well as limitation of great frontal sinuses and breadth of cheek to naso premaxillary region. Apart from these structural considerations, however, there are other cranial characters equally significant, which demonstrate that the family type of their skulls is not so entirely removed from each other as a hasty inspection is apt to infer. In Antilocapra, as in Oreas and some other Strepsiceres, the parieto-occipital is short compared with the very lengthened maxillo-premaxillary region. The orbit, subcircular, of fair size, if not large, has its optic axis directed outwards, and but very slightly upwards and forwards. The horn-cores, which stand erect, as in the Chamois, present, in this aspect, a broad dagger-shaped outline, and are implanted directly above the orbit, from its middle to beyond the rear. If the skull in this view be divided into five equivalent perpendicular segments, the occipito-temporal area would occupy one, the orbito-jugal region another, and the anterior three would consist of the lachrymal and naso-maxillary bones. In the erect-horned Rupicapra, where the occiput is short, the front of the orbit comes to about the middle of the skull. In many small Antelopes it reaches little short of this ; but in the Strepsicerine group the face is proportionally elongated, as in Antilocapra. In Deer, as a rule, the facial lengthening is considerable, as in the Prongbuck ; but there is this difference, that the postcranial segment is far greater than in the latter. From the top (fig. 6, A), excepting in the very different disposition of the horn-cores, the outline of the skull approaches less to the Giraffe than to most Cervidae, whilst it does not partake entirely of the Antelope features-even to the Strepsicerine group, which otherwise, in side view, have some points in common. A close resemblance can be traced, however, in the Sassaby (Damalis lunatus, H. Smith), though this Bovine Antelope markedly disagrees in possessing an elevated and not flattened intercorneal ridge. The individuality of upper contour in the Prongbuck's skull is iu some measure owing to the abbreviation of the parietal segment, moderate breadth of the frontals, increased, however, by the outstanding orbits, and by the long steadily continued naso-maxillary rostrum, which in most Antelopes and Deer has a decided wedge shape. The horn-cores, as seen looking down upon them, are broad and pass out far beyond the orbital periphery. The nutritious foramina at their base (s o f) are large and allow the light to descend quite through the orbit. The so-called supra- or anteorbital fissures |