STKUCTURE OF THE SPINAL COED. 



225 



white column. The anterior cornua are thick and the posterior slender. 

 The postero-mesial column is distinctly marked off. 



In the dorsal region the grey matter is small in amount, and both 

 cornua are slender (D 5). The whole cord is smaller in diameter than 



FIG. 256. TKANSVEKSE SECTIONS OF THE SPINAL CORD AT DIFFERENT LEVELS. 

 (Gowers.) (Twice the natural size.) 



The letters and numbers indicate the position of each section ; Ca, at level of coccygeal nerve ; 

 Sac. 4 of 4th sacral; L3 of 3rd lumbar, and so on. The grey substance is shaded dark and 

 the nerve-cells within it are indicated by dots. 



either in the cervical or lumbar region. The column of nerve-cells 

 known as Clarke's column, and the intermedio-lateral tract, are well 

 marked. 



In the lumbar region the crescents of grey matter are very thick, 

 and the white substance, especially the lateral columns, relatively small 



