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Show 362 DR. j. M U R I E O N T H E May 26, nasals narrow forwards much more and taper to a point, as in the Goats and Antelopes. 2. The supraorbital fissure is minute. 3. The supraorbital or antecorneal foramen is small. 4. The horns are round, more erect, and prongless. 5. The premaxillary does not articulate with the nasal. 6. The frontal region is much rounder and more highly arched. 7. The masseteric ridge ascends high before the orbit. H. It wants the anterior palato-maxillary valley so conspicuous in the Prongbuck. 9. The horizontal plate of the palate-bone is relatively shorter. 10. In the Chamois the palatine arch of the posterior nares is narrow and acute, in the Prongbuck widish and rounded. 11. In the first of these the basioccipital and the basisphenoid are much flatter than in the second. 12. The auditory bullae are very small and compressed, much more Goat-like by many degrees than are those of Antilocapra. 13. The paramastoid of the Chamois greatly exceeds that of the last-mentioned genus, and is more pointed. 14. The glenoidal articulation is convex to its outer edge, and the posterior transverse ridge is rudimentary. 15. The occiput is anti-lopine and not cervine in its character, inasmuch as it is prominently convex. 16. The condyles are rounded or not so sharply mesially ridged into a partially double facet as in the Prongbuck and Deer; and they jut rearwards and not so much downwards as in these. 1 7- The foramen magnum is decidedly very large. (e) Dentition.-As respects the deciduous dentition of the Prongbuck my observation is confined to a skull of an apparently adult animal in the College of Surgeons' Museum. In the said specimen, No. 3713, the three upper and lower deciduous premolars present (corresponding to the second, third, and fourth premolars of other Bovidae?) are partially uprooted and about to be replaced by their successors. The permanent successors seem nearly equally advanced ; the canines less so. Judging of the age of the animal by the character of the horns, I should be inclined to think the change of dentition in the Prongbuck coincidentally approximates to what obtains in the Sheep. The dental formula and series throughout are facsimiles of what is met with in the majority of Antelopes. The upper molars have smooth shallow outer concavities and low ridges. The hindermost tooth has a posterior tubercle. There are neither supplementary enamel columns nor lobules in these, nor in the lower molars. The median central crescents are of moderate size and simple. The premolars of the superior and inferior maxillae are fair-sized, increasing from the first to the third. The three mandibular true molar teeth have their longitudinal enamel ridges ill defined ; the concave internal depressions are very shallow. The outer lobes of the teeth are more angular than rounded. The crescentic fissures of the grinding-surface are simple. The incisors are sloping, subequal, and not equal-sized as Turner mentions; for the middle ones are moderately expanded at the tips and slightly larger than those outside. |
