168 OUTLINES OF EQUINE ANATOMY. 



being superiorly m contact with the temporal artery and 

 vem and facial nerve as they arise and wind round the 

 jaw, and then extends upwards over the muscles in front 

 of the ear forming one of its superior divisions, the 

 other being situated behind the ear. From this the j^os- 

 terior margin of the gland runs in a downward direction, 

 being separated from the wing of the atlas by tendinous 

 structure, and terminates at the junction of the submaxil- 

 lary and jugular veins, from which point its lower margin 

 runs forwards to the angle of the jaw. From this antero- 

 inferior point the duct of the gland arises, and passes over 

 the internal surface of the lower edge of masseter internus, 

 where it is covered only by panniculus and skin, and is 

 in company with the submaxillary artery, and the corre- 

 sponding vein. Through the substance of the parotid run 

 several large veins, among others the jugular, and by 

 raising it and removing the stylo-maxillaris, running from 

 the anterior part of the styloid process of the occiput to 

 the angle of the lower jaw, blending superiorily with digas- 

 tricus, we expose the termination of the 



Carotid artery. Just oj^posite to the commencement of 

 the trachea it breaks up into three parts, one. 



Ramus anastomoticus, runs directly upwards to the 

 under surface of the wing of the atlas (giving off a large 

 branch running to the occiput), here it rests upon obliquus 

 capitis anticus, and anatomoses with a vessel, the vertebral 

 artery, coming through the posterior foramen in the wing 

 ,of the atlas ; the trunk so formed passes into the anterior 

 foramen, which has two outlets, through one of which a 

 branch runs to obliquus capitis inferior upon the upper 

 surface of the atlas, through the other a branch passes 

 .into the spinal canal, and after piercing the dura mater 

 ;of the spinal cord anastomoses with its fellow from the 

 opposite side and runs forwards, as the basilar artery, to 

 supply the brain. The smallest of the three terminal 

 branches of the carotid, the internal carotid, runs directly 

 .towards the base of the cranium throughout its course 

 being situated with its fellow at the posterior part of the 

 septum formed by the contact of the internal walls of the 

 two guttural pouches. 



The external carotid seems to be the direct continuation 

 /Of the carotid trunk, it passes forwards, and just before 

 arriving at the posterior angle of the long cornu of os 



