THE NECK. 131 



The prominence of the cricoid cartilage can be seen in thin people and if care- 

 fully searched for can be felt in almost all cases. It is opposite the sixth cervical 

 vertebra, a most important landmark. From the cricoid cartilage down to the 

 sternum only soft structures can be felt. The sternum projects forward and the 

 trachea inclines backward so that opposite the top of the sternum the trachea is about 

 2 cm. behind it. The distance between the top of the sternum and cricoid cartilage 

 in an adult male is about 4.5 cm. (i24 in.). 



THE CERVICAL TRIANGLES. 



On viewing the neck from the side the prominent sternocleidomastoid muscle 

 with its thick anterior and thin posterior edge is seen to divide it into two spaces, 

 an anterior and a posterior. They are /called the anterior and posterior cervical 

 triangles. 



Cervical lymph- 

 nodes 



External jugular vein 



Submaxillary 

 lymph-nodes 



Submaxillary 

 gland 



Anterior belly of 

 digastric 



Submental 

 lymph-node 



Hyoid bone 



FIG. 163. Submaxillary region, superficial structures. (From a dissection.) 



ANTERIOR CERVICAL TRIANGLE. 



The anterior cervical triangle has for its anterior side the median line of the 

 neck. Its posterior side is the anterior edge of the sternomastoid muscle. Its upper 

 side is the lower edge of the mandible from the symphysis to the angle and thence 

 across to the mastoid process. The anterior triangle is further divided into the space 

 above the digastric muscle called the Submaxillary triangle, from its containing the 

 gland of that name, the superior carotid triangle above the anterior belly of the 

 omohyoid muscle, and the inferior carotid triangle below the omohyoid muscle. 



The SUBMAXILLIARY TRIANGLE is so called from its containing the Submaxillary 

 gland. It is also sometimes called the lingual triangle, from the lingual artery. It 



