QtrATEENAET PAUlSrA OP GIBEALTAE. 



119 



Unfortunately, as I have before observed, we possess at present but little available 

 material for osteological comparison between these two forms, except as regards 

 the skull. 



In the British Museum there is a specimen (No. 777 a) of the skull of a female 

 Pyrenean Ibex, of which the stuffed skin is also in the collection ; and there is another 

 skuU of an Alpine Ibex, which though young is quite mature, and its hom-cores are 

 of the same size as those of the Pyrenean skull. The two specimens therefore admit 

 of fair comparison. 



The relative dimensions of a few corresponding parts in these two skulls are as 

 under : — 



From these figures it will be seen that, so far as mere dimensions go, there is no 

 marked difference observable between the two, except in the greater length of the 

 malar bone in the Alpine Ibex, which is owing to the greater backward prolongation of 

 the zygomatic process, and in the greater length of the frontal longitudinal arc, which, 

 as compared with the somewhat greater length of the parietal, is worthy of notice. In 

 other respects the following points may be adverted to : — 



1. That in both forms the lower border of the lacrymal does not run parallel with 

 the lacrymal ridge of the malar, but forms a triangle with it below. 



2. That in the Alpine Ibex there is a deep depression or fossa around and in front 

 of the infraorbitary foramen, which is almost absent in the Pyrenean. 



3. That the premaxiUaries are slender in both. 



4. That the forehead is rather more hombe in the Pyrenean specimen, or more hol- 

 lowed above the root of the nasals. 



5. That the form of the ascending ramus of the mandible and the curvature of the 

 coronal process are alike in both. 



6. The horns have the same curve, and in both are angular on the inner side in front, 

 in the same way but not so marked as in Capra hircus, and that in the Pyrenean 

 specimen the horn is slightly hollowed on the inner face, as in the C. hispanica from 

 the SieiTa de Ronda. The Pyrenean horn is very closely and coarsely annulated in the 



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