XXIX.] SPINAL CORD. 803 



matter ; note the relatively small number of 

 nerve-cells in the anterior cornu of the dorsal 

 region. 



c. The quantity of white substance (number of 

 nerve fibres) is greater in the dorsal than in 

 the lumbar region, and greater in the cervi- 

 cal than in the dorsal, i.e. the quantity of 

 white substance in the cord increases from 

 below upwards. 



d. Iri the cervical region the posterior column 

 is divided into two parts, a median part, the 

 fasciculus of Goll, and a lateral part, the 

 fasciculus cuneatus, by a septum of con- 

 nective tissue (the fasciculus of Goll may 

 be traced some distance down the dorsal 

 region becoming smaller in its course). 



e. In the dorsal region there is a small lateral 

 collection of nerve cells in the grey substance 

 behind and laterally of the central canal; 

 this is Clarke's column, or the posterior 

 vesicular column. It becomes indistinct in 

 the upper dorsal and lower lumbar regions. 



/. In the dorsal region there is a lateral pro- 

 jection of the grey substance about mid-way 

 between the anterior and the posterior cornu, 

 this is the tractus intermedio-lateralis ; in it 

 is a group of nerve cells ; in the cervical and 

 lumbar regions this group of cells blends into 

 that of the anterior cornu. 

 L. 20 



