THE SPINAL CORD 



75 



This is again an arbitrary line of separation, since both as to external form 

 and internal structure the cord passes over into the medulla oblongata by in- 



Medulla oblongala 



f- N. cenicalis VIII 



' Ventral root of N. 

 T.I II 



Dorsal root of N. 



T.IV 



Lateral funiculus 

 Spinal dura mater 



- N. thoricalis XII 



\- Cauda equina 



I- N. lumbalis V 



Filum of spinal dura 

 mater 



.Medulla oblongata. _ 



I Anterior median fissure 



A nterolateral sulcus 

 -Cervical enlargement 

 -A nterior funiculus 



-Thoracic portion of- - 

 spinal cord 



I Lumbar enlargement 



Conus medullaris 



Filum terminale 



Rhomboid fossa 



Posterior median 

 sulcus 



Posterior funic- 

 ulus 



Posterior inter- 

 mediate sulcus 



Dorsal root 



- Spinal nerve 



. 



^-Cauda equina 



Fig. 50. Fig. 51. Fig. 52. 



Figs. 50-52. Three views of the spinal cord and rhombencephalon : Fig. 50, Lateral view 

 with spinal nerves attached; Fig. 51, ventral view with spinal nerves removed; Fig. 52, dorsal 

 view with spinal nerves attached. (Modified from Spalteholz.) 



sensible gradations. According to this method of subdivision there are in the 

 cervical portion of the cord eight segments, in the thoracic twelve, in the lumbar 

 five, and in the sacral five, while there is but one coccygeal segment. 



