THE ANATOMY OF THE OX. 



75 



the ox have these plexuses most largely developed. In the 

 giraffe there is scarcely a trace of the plexus, and in this con- 

 nection it should be said that this animal eats with its head 



Fig. 13. — The Heakt and Principal Vessels, Left Face. 



a. Right ventricle ; h. Left ventricle ; c. Right auricle ; d. Left auricle ; e. 

 Pulmonary artery ; e '. Obliterated arterial canal ; f. Pulmonary veins : g. 

 Anterior aorta ; h. Left axillary artery ; i. Right axillary artery, or brachio- 

 cephalic trunk ; j. Origin of the dorsal artery ; k. Origin of the superior 

 cervical artery ; /. Origin of the vertebral artery ; m. Origin of the inferior 

 cervical artery ; n. Origin of the internal thoracic artery ; o. Origin of the 

 external thoracic artery ; p. Carotid arteries ; q. Posterior aorta ; r. Anterior 

 vena cava ; s. Trunk of the axillary vein ; t. Trunk of the internal thoracic 

 vein ; u. Trunk of the dorso-cervical vein ; v. Posterior vena cava ; v '. Em- 

 bouchure of the hepatic and diaphragmatic veins ; x. Vena azygos ; y. Thoracic 

 duct ; z. Embouchure of that vessel, placed near the origin of the anterior vena 

 cava. 1. Right cardiac artery ; 2. Left cardiac artery ; 3. Auriculo-ventricular 

 branch of the left cardiac artery ; 4. Its ventricular branch ; 5. Cardiac vein. 



high up in the air, whereas most ruminants graze with their 

 heads near the ground. There is no definite bifurcation of the 

 carotid arteries in ruminants. 



There is a third longitudinal furrow running down the wall 



