| OCR Text |
Show 358 DR. J. MURIE ON THE [May 26, Each parietal (Pa, fig. 7, B) constitutes a broad but low arch ; the narrow anterior cresceirtic angle, as in other ruminants, goes down between the squamous postfrontal and orbito-sphenoid elements to meet the alisphenoid. The squamous element of the temporal bone, agreeably to the low form of the brain-case, is not deep. The convexity of the bone is moderate, and the upper sutural arch long and a little raised. The foramen, situated at the root, and upper surface of the zygoma, common to the Ruminants, in the Prongbuck, as in the An-tilopidae and Ovidae, is wide to excess ; and the perforation is seen to run superficially or within the diploii of the cranium, and to communicate with the mastoidal cells. The articulating surface or glenoid facet (gl), moreover, is more bovine- than cervine-shaped ; only that the bounding ridge behind and the tubercle and post-glenoidal ridge are not so prominently developed as in the former. The external auditory canal (Au) is large, and sticks upwards and backwards prominently. With the discrimination displayed in all his papers, the late Mr. Turner points out " that in the Moschidae and Cervidae the styloid process becomes free almost immediately at the base of the auditory process, while in the Bovidae or Cavicorn Ruminants it is enclosed more or less completely for some distance in the downward and forward direction." Antilocapra claims kindred with tbe latter family in the disposition of its styloid process, which is shortandensheathed. But, furthermore, the moderately enlarged tympanic (Ty) does not agree with that of its supposed ally, the Chamois, where it is remarkably triangular and compressed. Neither does it display a roundish inflated character as does the Antelopes', excepting the caprine group. On the contrary, in spite of the styloid ensheath-ment, the tympanic element of the Prongbuck, as far as my observations go, is singularly cervine or Goat-like in its development. The paramastoid process (Pmd) is short, moderately wide antero-posteriorly, and does not underhang or pass beyond the condyles. It is thick-rooted, or has a considerably high rough mastoidal eminence behind the auditory canal. I have alluded, in the general views of the skull, to the perpendicular character of the supraoccipital plane, and may further note that it is surmounted by a narrow transverse portion suturally connected with the parietals. The truncation of the supraoccipital (So) is not only very apparent, but it absolutely inclines forwards below. The spine and occipital protuberance are each well marked. The former is broad, moderately raised, and the muscular impressions on each side are deep rough concavities. The superior curved line forms a wide, sharp-edged, and regularly formed arch, terminating laterally in the short paramastoids, at the root of which posteriorly a short shallow groove is discernible. The condyles possess two distinct articular planes, which meet in a mesial raised acute line, whose direction is parallel with the posterior border of the paramastoid. Both facets, as in Deer, are relatively flat, the hinder one nearly vertical, the fore one directed ob- |
