62 UNIVERSITY OF MISSOURI STUDIES 



These suprarenal glands differ in their topography 

 from what is given by topographic anatomists in about the 

 same way as do the kidneys since the two organs are so 

 intimately connected. They do not have the characteristic 

 Y-shape in the projections because only the widest part of 

 the outline was measured in each plane. 



THE THYREOID GLAND 



The thyreoid gland, while not belonging to the thoracic 

 and abdominal viscera, was included in the projections in 

 order to show its relation to the lungs, trachea, oesopha- 

 gus, heart and great vessels. 



The left lateral lobe of the thyreoid is the larger and 

 extends from the middle of the ala of the thyreoid carti- 

 lage to the fifth ring of the trachea, or from the lower bor- 

 der of the fifth cervical to the middle of the second thoracic 

 vertebra. It is in relation internally with the larynx and 

 pharynx above, and with the trachea below; posterointer- 

 nally with the longus colli above and the oesophagus be- 

 low; posteroexternally with the common carotid artery and 

 internal jugular vein ; and anteroexternally with the sterno- 

 thyreoid muscle, and near the apex with the omohyoid 

 muscle. 



The right lateral lobe is shorter and broader than the 

 left. Its relation is about the same as that of the left 

 lobe except that being the broader it projects backward 

 over the side of the oesophagus more than the left one 

 (Plate III). 



The superior thyreoid vessels and recurrent laryngeal 

 nerves are to be seen in Plates III and IV, between the sur- 

 face of each lobe and the oesophagus. The lower part of 

 each lobe is separated from the apex of the corresponding 

 lung by the vessels and nerves of the region. 



