272 LABORATORY MANUAL OF HUMAN ANATOMY 



(n) Common carotid plexus (plexus caroticus communis). 



(o) Laryngopharyngeal rarni (rami laryngopharyngei). 



(p) Ascending pharyngeal plexus (plexus pharyngeus ascendens). 



(q) Superior cardiac nerve (N. cardiacus superior). 



(r) Middle cardiac nerve (N. cardiacus medius). 



(s) Subclavian loop (ansa subclavia [ Vieussenii] ) . 



(*) Inferior cardiac nerve (N. cardiacus inferior). 



(u) Subclavian plexus (plexus subclavius). 



(v) Internal mammary plexus (plexus mammarius internus). 



(w) Inferior thyreoid plexus (plexus thyreoideus inferior}. 



(x) Vertebral plexus (plexus vertebralis) . 



Note that all the above, except (a), (i), (o), (g), (r), (s), (t), 

 are plexuses about the larger arteries. 



Lateral Straight Muscle of the Head (M. rectus capitis lateralis). 



(Vide Spalteholz, Fig. 304.) 



Clean the muscle; find its origin and its insertion. What is 

 its action! What nerve supplies it? Find the ramus anterior of 

 the first cervical nerve. How is it related to the M. rectus capitis 

 lateralis? How is the first loop of the plexus cervicalis formed? 

 Divide the attachment of the M. rectus capitis lateralis close to 

 the transverse process of the atlas and turn the muscle upward. 

 Sever the origin of the M. obliquus capitis superior. Find the 

 nerve to the M. rectus capitis lateralis and follow it to its origin 

 from the first cervical nerve (N. suboccipitalis) . 



STRUCTURES IN FOSSA CEANII MEDIA. 



Removal of Dura Mater. 



(a) Cut through the dura mater just lateral from the openings through 



which the III., IV., and V. nerves pass, from the processus cli- 

 noideus anterior to the apex pyramidis (0. T. tip of petrous bone). 



(b) Cut through the dura mater from the apex pyramidis backward and 



lateralward along the line of the sinus petrosus superior as far as 

 the sulcus sigmoideus. 



(c) Cut through the dura from the processus clinoideus anterior lateral- 



ward and forward along the posterior margin of the ala parva of 

 the sphenoid bone to its lateral extremity. 



Lift the dura carefully, keeping the edge of the knife close 

 to the membrane, and thus avoid injury to the nerves attached 

 to it beneath. 



