ADVANCED EXPERIMENTAL PHYSIOLOGY 



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loiyngeal nerve and from the vagus; (Sy) the cervical sympathetic, 

 a slender thread, which must be traced up to the superior cervical 

 sympathetic ganglion. 



Follow the superior laryngeal nerve from the vagus to where it 

 enters the larynx, and likewise trace (Li) the inferior laryngeal nerve. 



Next divide the skin over the upper part of the sternum and reflect 

 the left skin flap. 



Pass threads round the sternal ends of the left first and second ribs. 

 Tie these and divide the ribs between the threads and the sternum, 

 Pull the ribs outwards by means of the threads, separate the inter- 

 costal muscles with the knife, and by cutting through the spinal 

 attachments of these ribs remove them. 



GE 



FIG. 230. Dissection of the stellate ganglion (GE) and cardiac accelerators. The 

 inferior cervical ganglion (CL) and vago-sympathetic (vs) are also shown. (Pn) vagus ; 

 (ac) carotid artery ; (asc) subclavian artery. (Dubois.) 



The stellate or first thoracic ganglion may now be found and cleaned 

 from the surrounding adipose tissue. It lies just in front of the spinal 

 attachment of the first rib. Branches enter the stellate ganglion from 

 the first, second, and third thoracic roots. Below the sympathetic 

 cord is attached to it, and above a nerve passes to it from the 8th 

 cervical root. The ganglion sends off branches, which form the 

 annulus of Vieussens, and pass to the inferior cervical ganglion. From 

 the annulus and from the inferior cervical ganglion branches pass to 

 the cardiac plexus. The stellate ganglion is the cell-station of these 

 accelerator and augmentor fibres. 



The stellate ganglion is also the cell-station of the fibres which pass 

 to the brachial plexus (vasomotor, pilomotor, sudoriferous) and to the 

 vertebral artery. 



