PUBO-FEMOEAL EEGION. 



141 



capsule being continuous with the posterior layer of the muscle 

 sheath — the deep layer of the triangular ligament. 



symphysis 



urethra 



constrictor urethrae 



Fig. 112. — The Constrictor Urethrae Muscle. 



IV. The inner sheath of the pyriformis forms the pyriform 

 fascia. As the muscle arises between the sacral foramina, the 

 sacral plexus lies within the sheath, the iliac vessels on its inner 

 aspect. The coccygeus is continuous with the levator ani and its 

 sheath forms part of the recto- vesical fascia. 



The Cervical Fascia. — From what has been said of the pelvic 

 fascia, the nature and arrangement of the cervical fascia will be 

 readily understood. It is composed of (1) the sheaths of the 

 cervical muscles (sterno-mastoid, etc.) ; (2) of the sheaths of 

 vessels (carotid sheath, etc.) ; (3) the sheaths of nerves (axillary 

 sheath, etc.) ; (4) the fascial capsules of viscera, such as the 

 thyroid body, salivary glands, and pharynx. 



