LUMBAE NERVES. 505 



Irachial plexus. It receives an anastomosing branch furnished 

 by the sisth nerve. 



The eighth cervical Tierve, larger than the preceding, also 

 passes to the brachial plexus. It sends a branch to the inferior 

 cervical ganglion. 



D0E3AL NERVES (17 pairs). 



The dorsal nerves, with the exception of the first, are all dis- 

 tributed in a similar and very simple manner, as compared with 

 the cervical nerves. The superior branches, passing up between 

 the transverse processes, bifurcate, one branch being sent to the 

 spinal muscles and the skin of the dorsal region, the other being 

 distributed to the longissimus dorsi muscle. The inferior 

 branches descend to the intercostal spaces, ::nd pass along 

 between the pleura and internal intercostal muscles. Each of 

 these intercostal nerves, at its origin, gives one or two branches 

 to the sympathetic, and, towards its middle, a perforatina branch 

 directed obliquely outwards to the skin, where it ramifies, pnd in 

 Its course, gives oflf muscular filaments. 



The inferior branch of the First Dorsal nerve goes almost 

 entirely to the brachial plexus. It has no cutaneous division 

 and uc intercostal branch is very slender. 



llie Second Dorsal nerve sends a large branch to the 

 bracbid plexus. Its intercostal branch, more considerable than 

 th.H of the first, extends down to the sternum, and gives off 

 cutaneous twigs. 



The Third, Fourth, Fifth, Sixth, Seventh, and Eighth 

 UOEs.^L NiaiVES pass to the extremity of the intercostal spaces 

 and are prolonged into the pectoralis magnus and rectus muscles • 

 tnetast mne, after reaching the cartilages of the false r.-bs are' 

 contmued into the walls of the abdomen, and under the internal 

 oblique, to the rectus, where they divide, one division going to 

 the substance of the muscles, the other furnishing twigs to the 

 skin of the abdomen. The Seventeenth Dorsal nerve fur- 

 nishes a large branch to the fleshy portion of the internal oblique, 

 and another which anastomoses with the first lumbar nerve. 



LUMBAR NERVES (6 pairs). 



The Superior branches of the lumbar nerves are distributed 

 to the muscles of the loins, and to the integument of the loins 

 and croup. 



