613 

 8737. The skull and horn-cores of a common Goat (Copra Hircus). 



The following differences may be noticed in comparing the skull of this species of Goat with 

 that of the Sheep (Otis Aries). In the Sheep the postorbital process or plate is broader and 

 more bent outwards, forming a deeper depression between it and the origin of the horn ; it 

 also turns the plane of the orbit more obliquely forwards : in the Goat the aspect of this plane 

 is more directly outwards. "With regard to the horn-cores, they are subcompressed, and flat- 

 tened at the postero-internal side in both, the transTerse section approaching a semi-ellipse in 

 shape, which is fuller in the Sheep ; the long axis of this semi-ellipse passes obliquely from 

 before outwards and backwards, but more outwards in the Sheep than in the Goat. In both, 

 the horn-core is sh'ghtly twisted as it ascends, so that the flat side is made to look more 

 directly backwards, but with a greater degree of curvature in the Sheep than in the Goat. 

 The horn-core is relatively longer in the Sheep, so that, after extending outwards, it bends 

 down and then forwards ; yet it differs from that of the Goat only in the extent and degree, 

 not in the direction, of the curvature : were the stronger and longer curve of the Sheep's 

 horn-core to be unbent, it would be brought to the curve characteristic of the Goat before 

 it was made straight. The occiput is higher in proportion to its breadth in the Goat than 

 in the Sheep. The petrosal is relatively longer and deeper in the Goat than in the Sheep ; 

 in both the stylohyal articulates with the petrosal. The nasals are relatively smaller in 

 the Goat, where they are shorter than the premaxillaries ; their upper surface is concave 

 lengthwise, except at the free points, where they are slightly bent down. In the Sheep the 

 nasals are relatively larger, are longer than the premaxillaries, and then- whole upper surface 

 is convex lengthwise. There are also differences in the connections of these bones ; in the 

 Sheep the nasals join the lacrymals and not the premaxillaries, whilst in the Goat they join 

 the premaxillaries but not the lacrymals, a vacuity, which is not present or is rudimental in 

 the Sheep, separating them from the lacrymals. In the Aoudad (No. 3780) the nasals pre- 

 sent, both in their form and connections, the characteristics of the Sheep. The upper border 

 of the maxillary bone is relatively shorter in the Goat, and the anterior border is not notched 

 to receive the upper end of the premaxillary, as it is in the Sheep. The premaxillary is 

 narrower at its alveolar end in the Goat, and its upper end rises so as to overlap the side of 

 the nasal : in the Sheep the premaxillary is relatively broader, and does not rise to touch the 

 nasal. The lacrymal bone of the Goat is shorter in proportion to its breadth, and is not im- 

 pressed on its facial surface by a lacryrnal fossa ; it does not touch the nasal : in the Sheep 

 the lacrymal is longer in proportion to its breadth, and is more regularly quadrate in form ; 

 it joins the nasal, and thus obliterates that vacuity which is present in the skull of the Goat ; 

 its facial plate is impressed by a concavity for the cutaneous lacrymal pit. The lacrymal 

 bone of the Aoudad resembles that of the Ovis Aries in both form and connections, but its 

 facial plate has no concavity for a cutaneous lacrymal pit. In comparing the upper contour 

 of the skull, from the transverse occipital ridge behind to the free extremity of the nasal bones, 

 we find it forming, in the Goat, nearly a right angle, with the two sides equal : in the Sheep 

 it forms a more open angle, with the anterior side twice as long as the posterior one. The 

 Ovis tragelaphus agrees with Ovis Aries in this character. 



Hunterian. 



