Cope.] 4-i [ Feb 21, 



wide shallow groove which extends anteriorly between the pterygoid 

 ala and the postglenoid process, and turning outwards round the latter, 

 grooves it. Opposite to the postglenoid process and just posterior to the 

 end of the pterygoid a small foramen enters, which is probably the for- 

 amen ovale. Almost continuous with it is a canal which pierces the base 

 of the pterygoid longitudinally, and issues in an excavation of its exter- 

 nal face near the sphenoid. 



The pterygoids are remarkable for their great length, enclosing as they 

 do with the palatine processes, a deep, narrow, trench-like fossa, which 

 measures almost the entire length of the zygomatic fossa. Processes of 

 the sphenoid contribute to these walls (which are thus double), and the 

 sphenoid roof is strongly concave. The alisphenoid is elongate antero- 

 posteriorly, and is principally in contact superiorly with the frontal; an- 

 teriorly it has a short suture with the lachrymal. Almost its entire length 

 is traversed by a shallow groove which terminates in a small foramen 

 opticum, opposite to a point marking the posterior third of the zygomatic 

 fossa. The foramen rotundum issues as usual between the alisphenoid 

 and the pterygoid, but is considerably anterior, as well as inferior to the 

 /. opticum. I cannot determine whether the orbitosphenoid is distinct. 



The lachrymal is a lai'ge bone of a triangular outline, the shorter 

 side being inferior. It is entirely on the inner face of the orbit, and 

 as in the elephant, separates the frontal and maxillary by its superior 

 prolongation. Its inferior border is slightly notched in front by the 

 large foramen infraorbitale posterius, and the anterior is deeply emargi- 

 nate, passing behind the small/, lachrymale. 



The palate is remarkable for its length and narrowness. Its roof is 

 chiefly composed of the mamillaries, but a very short portion is formed by 

 the palatine plates of the o. o. palatina. These are produced into a 

 median point behind between the nares, and exteriorly form the inner 

 wall of the postnareal trough for a considerable distance. The mamil- 

 laries also form the outer wall for a short distance, being produced in a 

 contracted form behind the molar teeth. The two bones enclose a small 

 foramen in this prolongation, and a larger one on the anterior suture of 

 the palatine, the foramen palatinum. The palate is deeply concave 

 anteriorly. There is an elongate foramen close to the alveolus of the first 

 premolar, extending anterior to it. The premaxillaries are longitudinal 

 and separated anteriorly for two-fifths of their length, by a large foramen 

 incisivum, which they do not enclose. They extend on the side of the 

 muzzle into an acute angle upwards and backwards and are prolonged 

 forwards above the exterior nares, which the suture reaches by an 

 abrupt descent. The maxillary supports the malar on a posteriorly 

 directed process which reaches to the end of the anterior third of the 

 arch below, half that distance on the side, and is bordered by a narrow 

 strip of the malar on the inner side, as far as the anterior boundary of 

 the orbit. The premaxillaries do not enclose the very large foramen in- 

 cisivum in front, and are therefore deeply furcate. 



