QUATBRNAET FAUTSTA OP GIBRALTAR. 121 



3. That the lacryinals are of the same length. 



4. That the malar is considerably longer in the Alpine Ibex, as before remarked. 



5. That the diameter of the orbit is somewhat greater in the Spanish Ibex. 



6. That in the other dimensions given there is no marked difference between the 

 two forms. 



If we proceed to compare the two forms in other respects, it will be found that 



1. In the Alpine Ibex the horn-cores are very slightly flattened on the inside, and 

 subangular though rounded behind ; that they diverge from their base, so that the 

 distance between the bases (at their centres) in front being three inches the points 

 diverge eight inches, and that they exhibit no sign whatever of torsion. In the Spanisli 

 Ibex from the Sierra de Gredos the cores are slightly angular on the inner side behind 

 and not at all flattened, and they have a decided indication of torsion. Also they rise 

 more parallel to each other at first, and then diverge, so that the interval between their 

 respective centres at the base being 3"'3 the tips are 6"'8 apart. The difference in their 

 shape is very distinct and marked. 



2. In the Alpine Ibex the inner or lower border of the lacrymal is more curved, 

 owing to its running parallel (or being, in fact, almost coincident) with the malar sub- 

 orbital ridge, whilst in the Spanish Ibex the border is straighter, and there is left 

 inferiorly a triangular interval between it and the malar ridge in question. 



3. In the Alpine Ibex there is a wide and deep depression around and in front of the 

 infraorbitary foramen in the maxillary, which is almost entirely absent in the Spanish 

 Ibex from Sierra de Gredos (E.C.S.), and much smaller though deep in 3743 c. 



4. The forehead is rather more bombe in the Alpine Ibex. 



5. The zygomatic process of the malar is much more produced in the Alpine Ibex. 



6. The mandible is perhaps slenderer in the Spanish Ibex, and the coronoid process 

 less recurved. 



7. The diameter of the orbit is rather greater in the Spanish form. 



8. The premaxillaries are thicker, especially towards the apex. 



9. The fronto-nasal suture in the Spanish Ibex is a uniform semicircle, whilst in the 

 Alpine it forms three sides of a hexagon. 



On our return from Gibraltar Dr. Falconer and myself examined a specimen of 

 Co.pra hisjjanica in the Museum at Cordova, stated to belong to a young male. In 

 this the horn-core was 8 inches long, and had a basal circumference of 6"-2, so that it 

 was of enormous proportional thickness. It had a well-marked angle on the inner 

 side, which began at the posterior border of the base, and, gradually advancing in front, 

 was lost about two thirds up. On October 25, 1865, Dr. Falconer, after I had left 

 him in the south of France, compared at Montauban three skulls of what was styled 

 Ca'pra fyrenaica, from the Museum of Toulouse, with some of the bones brought by 

 us from Gibraltar, and found, except for difference in size and age, that they agreed in 

 the closest manner. 



