MAMMALIA. 



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proceeding from the superior cervical ganglion communicate with the ninth and sub- 

 occipital nerves and the pharyngeal plexus, and send a very large branch on the 

 carotid artery for supplying the salivary glands, and other parts on which the arterial 

 branches are distributed. In the porpoise the pyriform superior cervical ganglion of 

 the sympathetic nerve sends one portion upwards ; the prolongation is continued 

 downwards, and just below the superior cervical ganglion communicates with the 

 superior laryngeal nerve ; at the lower part of the neck, the prolongation terminates 

 in the second or inferior cervical ganglion ; on the right side, but not on the left, this 

 communicates with the par vagum at the place from which the superior cardiac nerve 

 is given off; there is also another communication of the par vagum with this ganglion. 

 The prolongation from the superior cervical ganglion is usually a small cord ; in 

 the baboon and monkey generally, but not always, and in the hedgehog and rabbit it 

 passes down the neck to the inferior cervical and first thoracic ganglia, without any 

 intimate attachment to the trunk of the par vagum, and distributes branches in its 

 course, but in the baboon it sometimes forms a close union with the nerve for about 

 a third of an inch, just below the superior cervical ganglion. In the pig, it only just 



joins the par vagum on the right side, and for a very short distance on the left, before 



_ 

 it passes to the inferior cervical ganglion, which is quite separate on the right side, 



but joined to the first thoracic on the left. In many animals, as the jaguar, dog, fox, 

 ass, calf, and goat, the prolongation through the neck is attached to the trunk of the 

 par vagum, and in the calf has sometimes very small ganglia imbedded in it, which 

 give filaments to accompany small arteries ; it leaves the trunk of the par vagum 

 sooner or later at the bottom of the neck to form the inferior cervical ganglion, and 

 become connected with the first thoracic. There is a plexus on each side of the 

 neck continuous with the cardiac nerves in the baboon and rabbit, but it is not so 

 complicated as in man ; it receives from the superior cervical ganglion a slender 

 branch, which is joined by a filament from the superior laryngeal nerve, and at the 

 bottom of the neck by other branches from the sympathetic, the par vagum, the 

 recurrent, and phrenic : communications then take place between the nerves of the 

 two sides, and branches are sent to the heart, those connected with the right side 



