444 



DR. C. F. SOXNTAG OX THE 



The Organs of Respiratiox. 



Larynx. — The epiglottis is qiiadritngular, with rounded angles, 

 and is attached to the tongue by a prominent glosso-epiglottic 

 fold. At its base, just above the false cords, a transverse slit 

 leads into a cavity formed by the excavated hyoid bone. From 

 the right side of the cavity a laiyngeal sac protrudes. The false 

 cords are thick, the true ones are thin, and the ventricles are 

 deep. The arytenoids are prominent. The upper border of the 

 thyroid cartilage has two small elevations for articulation with 

 the hyoid. 



The trachea has twenty-four rings which are all incomplete 

 behind. 



Lungs. — The left lung has two lobes, and the right one has 

 four, of wdiich one is the azygos appendage. 



The Nervous System. 



The Glosso-'pharyngeal Nerve (text fig. 19, ix) has the usual 

 relations to other nerves at the base of the skull, and it com- 

 municates with the vagus, hypoglossal, and sympathetic. It 

 winds round the st3do-li3'oid ligament, runs antero-mesially, and 

 breaks up into lingual nerves which disappear under the hyo- 

 glossus. It sends branches to the pharyngeal and carotid 

 plexuses (P.P and C.A.P), the tonsil, and soft palate. 



Text-fi£fure 19. 



The nerves in the anterior part of the neck. L.B.T : lingual branch of the 

 trigeminal ; L.A : lingual artery. Other letters in text. 



The Vagus Nerve (text-figs. 19-21) is separate from the 

 sympathetic in the neck. And its course in the neck and thorax 

 is similar to that already described in m}'- papers on the Mar- 

 supialia. The ganglion nodosum (text-fig. 19, G.N) is well 

 marked on each .side and the following branches are e-iven off- 



