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(/) The great auricular, arising from the third cervical nerve, an J running 

 from the under surface of the sterno-mastoid muscle to the ear, 

 where it divides into two branches. 



3. The trachea. Clear away the muscles connected to it and raise it up. 



Note its rings of cartilage, incomplete on their dorsal aspect ; the 

 larynx, at its upper extremity ; and its bifurcation to form two 

 bronchi posteriorly. Trace the bronchi to tlie lungs. 



4. The thyroid gland, made up of an elongated lobe on each side of the 



trachea below the larynx, connected by the isthmus which lies in 

 contact with the trachea. 



5. The larynx, at the upper extremity of the trachea. Observe the following 



parts connected with it : — 



(a) The epiglottis, at the root of the tongue, forming a covering for the 



glottis. 



(b) The large thyroid cartilage. 



(c) The cricoid cartilage. 



Make a longitudinal section in the middle line, and in the interior 

 of the larynx note — 



(d) The arytenoid cartilages, mounted on the posterior portion of the 



cricoid. 



(e) The true vocal cords, stretching from the arytenoid cartilages to be 



inserted on the inner aspect of the thyroid cartilage. 

 (/) The false vocal cords, above, and parallel to, the true vocal cords. 

 ((/) The ventricles of the larynx, shallow pockets between these. 

 {h) The glottis, the opening between the vocal cords. 

 G. Cat through the symphysis of the lower jaw, and remove the left half of 

 the jaw from its articulation with the skull. Dissect out the paired 

 salivary glands. Note — 



(a) The parotid, a large gland, underneath, and in front of, the outer ear: 



trace its duct (Stenson's) from the anterior part of the gland to 

 its opening in the cheek near the second upper premolar tooth. 



(b) The sub-maxillary, a more compact gland, near the angle of the jaw 



and internal to the parotid. Trace its duct (Wharton's) from the 

 posterior portion of the gland to its opening on the floor of the 

 mouth between the lower incisors and the root of the tongue. 



(fi) The sub-lingual, an elongated gland, lying along the inner border of 

 the ramus of the jaw. It has many ducts opening singly. 



(d) The infra-orbital gland, found just above the zygoma. Trace it 

 downwards underneath the zygomatic arch, and observe its duct 

 opening far back in the mouth. 

 7. Examine the buccal cavity, and note — 



(a) The roof of the mouth, formed of the transversely corrugated hard 

 palate and the smooth soft palate. Observe the teeth (to be 

 afterwards studied) ; the naso-palatine canals, two small apertures 

 behind the second incisor teeth ; and the tonsils, near the termi- 

 nation of the soft palate. 



