94 ANATOMY OF THE RABBIT 



Method: Transect the sternomastoid (7) and sternothyroid (61) 

 muscles, if these muscles were dissected on the other side 

 earlier, but it is not necessary to transect the sternohyoid 

 muscle (62) since simply pushing it to the right side of the 

 trachea will give ample working room. 



The internal jugular vein, the common carotid artery 

 (30) and the tenth cranial (pneumogastric or vagus) nerve lie 

 closely parallel along the trachea. The pneumogastric nerve 

 may be stained red from dye diffused out of the common carotid 

 artery. 



30. Common carotid artery (Fig. 26): Innominate; 

 branches to head and neck. The origin of the common carotid 

 will be studied when the thorax is opened (Chapter X). 



31. Internal carotid a.: Common carotid; to internal 

 structures of cranium. This branch leaves the common carotid 

 at a point near the base of the skull and passes into the cranium 

 through the lacerum medium foramen. 



32. External carotid, a.: Common carotid; to soft struc- 

 tures outside of cranium and to bones of skull. The external 

 and internal carotids anastomose with each other and with 

 branches of the vertebral a. {^^) within the cranium (Fig. ^^. 



