CHAPTER VIII 

 THE SPINAL CORD AND ITS NERVES 



THE spinal cord (medulla spinalis) is the least modified part 

 of the embryonic neural tube, and the spinal nerves constitute 

 the only part of the nervous system in which the primitive seg- 



Posterior divisio 



Rami communicantes 

 Sympathetic ganglion 



Anterior cutaneous n. 



Fig. 55. Diagram of a typical spinal nerve in the thoracic region. 

 The spinal column and the muscles are shown in gray, the nerves and their 

 ganglia in black. (Modified from Gray's Anatomy.) 



mental pattern is clearly preserved in the adult body (see p. 

 113) The spinal nerves are connected with the spinal cord in 

 serial order, a pair of nerves for each vertebra of the spinal 

 column (see Fig. 41, p. 107). 



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