MAMMALIA. 151 



accessory and to the trapezius muscle, and then pierces this to terminate on the skin 

 at the lowest part of the neck. The posterior trunk of the first cervical nerve gives 

 branches to the splenius, complex, and other muscles, close to the posterior part of the 

 spine, and then sends a branch through the complex towards the occiput, which gives 

 filaments to the muscles inserted into the back of the ear, but is chiefly distributed on 

 the skin of this part. The posterior trunk of the second, after giving branches to the 

 splenius, complex, and other muscles, close to the posterior part of the spine, also 

 sends a branch through the complex muscle to the skin of the occiput. The posterior 

 trunk of the third gives branches to the complex and other muscles close to the spine, 

 and then terminates on the skin. The posterior trunks of the fifth and sixth also give 

 branches to the muscles and skin ; the seventh was traced to the muscles only ; the 

 three last are much smaller than the preceding. In the fox, the phrenic nerve is 

 formed of a branch from the fourth and fifth ; it passes over the pericardium to the 

 diaphragm, and on the right side is placed close to the inferior vena cava. In the ass, 

 the nerve given to the great serrated muscle, proceeds from the fifth cervical nerve 

 with the phrenic ; but the phrenic afterwards communicates with a branch of the sixth, 

 given to the great pectoral muscle. In the jaguar, the phrenic arises from the fourth 

 and fifth cervical nerves, and receives a branch from the first thoracic ganglion of the 

 sympathetic. In the fox, the axillary plexus is constituted of the three inferior cervical 

 and the first dorsal nerves, but the greatest part of the fifth, after receiving a branch 

 from the sixth, gives a large branch to the integuments on the anterior part of the 

 shoulder joint, and then passes to form the superior scapular nerve, and terminate on 

 the superior and inferior spinous muscles. Branches from the fifth, sixth, and seventh 

 cervical, and first dorsal, are given to the pectoral muscles ; a branch from the sixth 

 cervical is given to the great serrated muscle, and branches from the fifth and sixth to 

 the sub-scapular. A branch from the seventh cervical nerve passes down the side to 

 the cutaneous muscle and skin, and communicates with the external branches of 

 several of the dorsal nerves. The circumflex nerve arises from the union of the fifth 

 and sixth cervical nerves, gives branches to the sub-scapular and teres muscles, and 

 then divides and sends a branch to the inferior spinous muscle and the deltoid, and 



