356 THE SPINAL CORD, BY J. GERLACH. 



and immediately behind the white commissure (fig. 226, t), 

 are the anterior commissural fibres of the grey substance 

 (fig. 226, h). To the right and left of, as well as behind, 

 the central canal is the fine nerve-fibre plexus (fig. 226, /), 

 behind which are the posterior commissural fibres that (fig. 

 226, g) immediately bound the sulcus longitudinalis posterior 



Fig. 226. 



Fig. 226. Median portion of a transverse section of the spinal cord 

 of a Child six months old, from the lower part of the cervical region, 

 treated with double chloride of potassium and gold. Magnified 50 

 diameters, a a, Anterior columns ; b 6, posterior columns ; c, cen- 

 tral canal ; d, line indicating the epithelium of the central canal ; e, 

 connective tissue surrounding the central canal ; /, nerve-fibre plexus 

 around the central canal ; g, posterior transverse fibres of the grey 

 commissure; h, anterior transverse fibres of the grey commissure; 

 i, decussation of fibres in the anterior white commissure. 



in the middle line, and the posterior columns laterally (fig. 

 226, 66). 



The central canal is not everywhere of the same form, 

 being somewhat oval transversely in the cervical region, whilst 

 in the dorsal region it is more rounded, and in the lumbar 

 region more cordiform in shape ; it commences in the floor of 



