ANATOMY IN A NUTSHELL. 



305 



the Levator anguli scapulae and the Scalenus medius muscles and under the 

 Sterno-cleiclo-m ast o id . 



The branches of this plexus are superficial and deep. The superficial 

 ones divide into ascending and descending, while the deep divide into internal 

 and external. 



The ascending branches are, (1) small occipital. (2) great auricular, (3) 

 transverse cervical (this branch is sometimes called a transverse branch instead 

 of an ascending branch). 



The descending branches are also three, which come from one main trunk — 

 the supraclavicular. These branches are, (1) suprasternal, (2) supraclavicular, 

 and (3) supra-acromial. 



The internal branches are, (1) communicating, (2) muscular, (3) communi- 

 cans hypoglossi, (4) phrenic. 



PLATE CXXXVII. 



EPIGLOTTIS 



HYOID BONE 

 'CUSHION OF EPIGLOTTIS 

 THYROID CARTILAGE 



THYRO- ARYTENOID 



CRICOID CARTILAGE 



m 



li|j_FALSE VOCAL CORD 

 LARYNGEAL SINUS 



TRUE VOCAL CORD 



True and False Vocal Cords. 



The external branches are, (1) communicating, (2) muscular. 



The small occipital nerve (Plate CCXVI) is sometimes double and it varies 



in size. This nerve is derived from the second cervical nerve (and third) and 

 :it'u !• passing to the back of the posterior border of the Sterno-cleido-mastoid, 

 it passes along this muscle to the mastoid process of the temporal bone where 

 it perforates the deep fascia and passes into the superficial fascia of the scalp. 

 It breaks up into three branches. (1) An auricular branch which supplies the 

 integument on the inner and upper part of the pina. (2) A mastoid branch 

 which is distributed to the integument on the mastoid process. (3) Occipital 

 branches which are distributed to the integument of the scalp and communi- 

 cate with the great occipital, great auricular, and posterior auricular nerves. 



The great auricular nerve (Plate CCXVI) is derived from the second and 

 third cervical nerves and after passing to the posterior borderof the Sterno- 

 deido-mastoid, it perforates the deep fascia and ascends upon this muscle be- 

 neath the Platysma to the parotid gland. This nerve lies almost parallel with 



