34 OREODON. 



At the inner side of tlic entrance of the infra-orbital canal, are two foramina, 

 homol()"-oiis with the posterior palatine and spheno-palatine foramina. 



Another foramen,, the anterior orlntal, is situated in the suture between the 

 lachrymal and palate bone, alwut half way between the entrance to the infra-orbital 

 canal, and the lachrymal margin of the orbit. 



The foramina spheno-orbitale and rotundum, form one large and vertically oval 

 foramen, which is situated just within the pyramidal process forming the terminal 

 conjunction of the temporal and pterygoid surfaces. 



The optic foramen is situated some distance in advance of, and slightly above 

 the position of the spheno-orbital, is about one-third the size of the latter, and is 

 also vertically oval. 



The bones which contribute to the construction of the orbit are the lachrymal, 

 frontal, superior maxillary, malar, palatal, and anterior sphenoid. 



Form, Relations, and Connections of the Bones of tlie Skull. — The occipital bone 

 posteriorly, is trilateral with a prominent apex, and it terminates by its other angles 

 in the long paramastoid processes. 



The lambdoidal suture commences at the outer side of the base of the latter, and 

 ascends posteriorly between the occiput and the process from the pars j^etrosa, and 

 then advances over the occipital ci'est to the side of the cranium between the occipital 

 and parietal bones. It is serrated, and at the occipital summit it forms a trifoliate 

 line. 



The spheno-basilar connection is not obliterated in the adult specimens under 

 investigation, but is elevated and distinct. 



As in the Camel, the squamous portion of the temporal bone, from its great 

 relative size to that of most other animals, is a striking feature in the anatomy of 

 the temporal fossa. 



The squamous suture forms about three-fifths of an oval outline, and is pretty 

 strongly serrated as in ruminants generally. 



Between the pars squamosa and the occiput posteriorly, is a narrow process from 

 the pars petrosa, ascending from between the mastoid process and the base of the 

 paramastoid, to the conjunction of the occipital with the parietal bones. To the 

 pars squamosa and occiput, it is connected by serrated suture. 



As in all ruminants, there is only a single parietal bone; and, as in the Camel, 

 this is remarkable for its length in comparison with that of more ordinary mem- 

 bers of the family. It is narrowest posteriorly, and gradually widens to the ante- 

 rior portion of the squamous suture, where it descends to the wings of the post- 

 sphenoidal bone. Anteriorly it is deeply notched for the reception of the posterior 

 part of the ossa frontis. 



The body of the post-sphenoidal unites with that of the ante-sphenoidal on a 

 line with the spheno-orbital foramina. 



The wing of the ante-sphenoidal bone articulates with the vertical plate of the 

 palate bone, the frontal, a small portion of the parietal, and the wing of the post- 

 sphenoidal bone. 



The external pterygoid process is united with the internal, as in the Sheep and 



