282 



PHYSIOLOGY 



CHAP. 



and in the relative quantity of grey and white matter, particularly 

 in the region of the cervical and lumbar enlargements. 



By means of Otto Stirling's table of planimetric measurements 

 of the cross-sections of single spinal roots, of the grey and white 

 matter, and of the different bundles at the level at which each root 



FIG. 170. Transverse section of spinal cord at different heights. (W. B. Growers.) Twice the 

 natural size. The letters and numbers indicate the position of each section ; Co, at level 1 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. 



emerges, Woroschiloff constructed the diagrammatic curve of 

 Fig. 171, in which the abscissa represents the points at which the 

 roots emerge, while the ordinates indicate the sectional areas of 

 the grey matter, the roots, and the different columns (dorsal, 

 lateral, ventral). The first curve (gr) shows the increase of grey 

 matter near the lumbar and cervical enlargements. The second 



