DISSECTION OF THE HEAD AND NK< K 



I'll 



1. Sternomastoid portion. 



2. Parotid portion. 



3. Submaxillary portion. 



4. Median suprahyoid portion. 



5. Median infrahyoid portion. 



6. Supraclavicular portion. 



The Middle Part (Fascia colli, deep layer] ("omoclavicular aponeurosis" 



of Richet). 

 Extent. 



Vertically, from os hyoideum to thorax. 

 Laterally, from one M. omohyoideus to the other. 



FIG. 89. 



Sheath of the. 



scalene 



muscles 

 Adipose mass 



Space behind 



the fascia 



praeverte- 



bralis 



I'rrviseeral --' 

 space 



Superficial sub- 

 aponeurotic space 



...Visceral sheath 



The interaponeurotic spaces, seen in section and supposed to be injected. The visceral and vascular 

 sheaths, the sagittal septa, and the fascia praevertebralis are represented by dotted lines, the middle 

 aponeurosis by a heavy black line. The section passes immediately below the larynx. (From Poirier 

 ct Charpy, Traits d'Anat. hum., Paris, 1901, 2 ed., t. ii. p. 426, Fig. 269.) 



Embedded in it are the omohyoid, sternohyoid, cleidohyoid, 

 and thyreohyoid muscles. In lower forms this fascia is repre- 

 sented by a single broad cleidohyoid muscle; in man it has 

 become differentiated into several muscles with connective tissue 

 between. (Gegenbaur.) 



