228 LABORATORY MANUAL OF HUMAN ANATOMY 



(2) From the lower half of the dome to the visceral sheath of 



the deep cervical fascia (pretracheal aponeurosis). 



(3) From the sixth and seventh cervical vertebrae to the first 



rib, often replacing the M. scalenus minimus. This is 

 the ligamentum costopleurovertebrale. 



(4) From the anterior surface of neck of first rib to anterior 



surface of cupula. This is the ligamentum costopleu- 

 rale. 



The two latter ligaments may be absent altogether. 



(b) Apex of lung (apex pulmonis). 



(c) Trachea, 



(d) Oesophagus. 



Cervical Plexus. (Vide Figs. 90 and 122.) 



The cervical plexus (plexus cervicalis) should now be studied. How 

 is it formed ? What is its relation to the brachial plexus ? What are its 

 exact situation and relation to surrounding parts? What muscles re- 

 ceive their innervation from it? Review the communications formed 

 by the cervical plexus with the cerebral nerves (N. hypoglossus, N. 

 vagus, N. accessorius) . How is the sympathetic nervous system related 

 to the cervical plexus ? Make drawings or diagrams to show the cervical 

 plexus and its relations as they exist in your cadaver. 



General Review of Blood-vessels of Side of Neck. 



The dissector should now make a systematic review of all the blood- 

 vessels of the side of the neck, reading on the structures from his text- 

 book and making a sketch of the large arteries and their branches and 

 the large veins and their tributaries. 



Further Study of Viscera of Neck. 



(a) Thyreoid gland (glandula thyreoidea). 



(aa) Isthmus of thyreoid (isthmus Gl. thyreoideae) . 



(ab) Pyramidal lobe (lobus pyramidalis) (inconstant). 

 (oc) Right and left lobes (lobi dexter et sinister). 



(ad) Lobules of gland (lobuli Gl. thyreoideae) . 



(ae) Stroma of gland (stroma Gl. thyreoideae}. 



Are any accessory thyreoid glands present? 



(b) Trachea. 



(ba) Tracheal cartilages (cartilagines tracheales). 



(bb) Annular ligaments (Ligg. annulares trachealia). 

 (be) Membranous wall (paries membranacea) . 



(c) Cervical part of gullet (oesophagus, pars cervicalis). 



BACK OF HEAD, NECK, AND TRUNK. 



The dissectors of the head and neck work in conjunction with 

 those of the upper extremity. 



Make an incision in the middle line from the inion to the 

 spine of the vertebra prominens, a second from the spine lateral- 

 ward to the medial border of the acromion, and a third from the 

 inion transversely lateralward (vide Fig. 3). Reflect the skin, 



