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DISSECTION OF DEEP VESSELS AND NERVES OF NECK. 



Dissection 

 of rectus 

 lateralis. 



Rectus 

 lateralis : 



parts 

 around 



Dissection 

 of first 

 nerve. 



Anterior 

 division of 

 suboccipital 

 nerve 



lies on atlas 



forms a loop 

 with 

 second : 



branches. 



Sympathetic 

 nerve in 

 neck 



has three 

 ganglia. 



Other 

 ganglia on 

 fifth nerve. 



Dissection 

 of upper 

 ganglion ; 



tongue except the palato-glossus, and to all the intrinsic muscles o: 

 the tongue. 



Dissection. The small rectus capitis lateralis muscle, between th< 

 transverse process of the atlas and the base of the skull, is now to be 

 cleaned and learnt. At its inner border the anterior branch of the 

 first cervical nerve, which forms a loop in front of the atlas, is to be 

 found. 



The RECTUS CAPITIS LATERALIS is very short, and represents 

 posterior intertransverse muscle. It arises from the fore and uppei 

 part of the transverse process of the atlas, and is inserted into the 

 jugular process of the occipital bone. 



On the anterior surface rests the jugular vein ; and in contact with 

 the posterior are the obliquus superior muscle and the vertebral artery. 

 To the inner side lie the anterior primary branch of the first cervical 

 nerve and the rectus anticus minor muscle. 



Action. It assists the muscles attached to the mastoid process in 

 inclining the head laterally. 



Dissection. For the purpose of tracing backwards the anterior 

 branch of the first cervical nerve, divide the rectus lateralis muscle, 

 observing the offset to it ; then cut off the end of the transverse pro- 

 cess of the atlas, and remove the vertebral artery, so as to bring into 

 view the nerve as it lies on the first vertebra. 



The ANTERIOR PRIMARY BRANCH OF THE FIRST CERVICAL, or SUB- 

 OCCIPITAL, NERVE is rather smaller than the posterior, and arises from 

 the common trunk on the neural arch of tl.e atlas. From that spot 

 it is directed forwards above the transverse process, and on the inner 

 side of the vertebral artery, to the interval between the rectus 

 lateralis and rectus anticus minor muscles. Emerging here, it bends 

 down in front of the transverse process of the atlas and forms a 

 loop with the second cervical nerve. As the nerve passes forwards 

 it supplies the rectus lateralis and anticus minor muscles, and 

 branches connect the loop with the vagus, hypoglossal and sympathetic 

 nerves. 



SYMPATHETIC NERVE. In the neck the sympathetic nerve consists, 

 on each side, of a gangliated cord, which lies close to the vertebral 

 column, and is continued into the thorax. On this portion of the 

 nerve are three ganglia the superior near the skull, the middle 

 towards the lower part of the neck, and the inferior close to the first 

 rib. From the ganglia proceed connecting branches to the spinal 

 and most of the cranial nerves in the neck, and branches for 

 distribution to viscera and blood-vessels. 



Besides the ganglia above mentioned, there are other ganglia in 

 the head and neck, where the sympathetic enters into connection 

 with the three divisions of the fifth nerve. 



Dissection. To display the branches of the sympathetic nerve 

 greater care is necessary than in tracing the white-fibred nerves, for the 

 sympathetic twigs are softer, more easily torn, and generally of smaller 

 size. In the neck the ganglia and their branches have been partly 

 prepared, and only the following additional dissection will be required 



