THE YEIXS. 395 



veins carry the blood to the heart, I shall describe them as 

 commencing by their branches and running toward the heart. 

 I shall take up but little space with them, only pointing out a 

 few of the principal trunks. Nearly every artery has its cor- 

 resjDonding vein in the same neighborhood. The veins lie 

 much nearer the surface or outside, generally, than the arteries. 

 The walls of the veins are soft, and when the blood is out of 

 them they collapse, or the sides fall together. 



The Veins of ilie Head and Neck. — Imj^ortant branches run 

 along the bars of the mouth, which are opened sometimes for 

 the purpose of bleeding. Of the branches coming from the 

 face, six from the upper part unite Avith the internal maxillary 

 vein^ and eight from the lotver jaw with the submaxillary. 

 These two unite with the jugular "vein, or great vein of the 

 neck. Eleven other branches, from the head, neck, and inner 

 part of the shoulder, empty into the jugular vein. 



The jugular vein passes from behind that part of the lower 

 jaw which unites with other bones below the ear to form the 

 joint. It then passes back by the side of the carotid artery, 

 to within the chest, where it unites with the vena cava, (ante- 

 rior or forward vein), which empties into the right auricle of 

 the heart. 



There are two jugular veins in the horse, one on each side 

 of the neck. It is the jugular vein which is opened in bleed- 

 ing, a little way below where the submaxillary vein unites with 

 it, and which is about one-third of the way back on the neck, 

 wdiere the vein comes close to the skin. 



Another large vein arises from branches within the skull, 

 and passes back along the neck-bones, receiving branches from 

 the deep muscles, and finally empties into the anterior vena caA^a. 



Veins of the Fore-limb. — These commence in the foot by 

 many hundred branches, Avhich are the A^eins of the frog, sole, 

 and lamellae, and other parts Avithin the hoof. These unite as 

 they reach the pasterns on their upAvard course, forming the 

 two branches of the plantar vehiy Avhich unites with other veins 



