138 Miss M. P. FitzGerald. The Lumbosacral-coccygeal [June 17 , 

 Thus it is seen that : — 



(1) In sectional area, both the white substance as a whole, and the ventro- 

 lateral and dorsal columns, increase with the cord from the first to the 

 fourth lumbar region, and decrease together with the cord from the fourth 

 lumbar to the third coccygeal region. 



(2) The increase in the white substance is relatively less than that in the 

 cord, whereas the decrease is relatively greater. 



(3) Of the white substance, both the ventro-lateral and dorsal columns 

 increase relatively less than the cord, and decrease relatively more to the 

 second coccygeal region. From this region the decrease in the ventro- 

 lateral columns is relatively less than that in the cord, though the decrease 

 in the dorsal columns continues to be relatively greater. 



(4) The ventro-lateral columns increase relatively rather more than the 

 dorsal columns, and decrease relatively less. 



(5) The decrease in the dorsal columns is relatively greater than the 

 decrease in any other component part of the cord. 



(6) In sectional area, both the grey substance as a whole, and the ventral 

 and dorsal horns, increase with the cord and white substance, from the first 

 to the fourth lumbar region, and continue, to increase to the fifth lumbar region, 

 whilst the cord and white substance are decreasing. The grey substance and 

 the ventral and dorsal horns decrease with the cord and white substance 

 from the fifth lumbar to the third coccygeal region. 



(7) The increase of the grey substance is relatively much greater than the 

 increase of the cord, and is still greater than the increase in the white 

 substance. The decrease is relatively less than that of the cord, and much 

 less than that of the white substance and its component parts. 



(8) Of the grey substance, both the ventral and dorsal horns increase 

 relatively more than the cord, the white substance and its component parts. 



(9) The increase in the " ventral horns " is relatively much greater than 

 that in any other component part of the cord, and is considerably greater 

 than the increase in the " dorsal " horns. 



(10) The ventral horns decrease in much the same proportion as the cord 

 (or relatively rather less to the seventh lumbar region and subsequently 

 rather more). They decrease relatively less than the white substance and 

 its component parts, to the second coccygeal region, where the decrease 

 becomes relatively greater than the decrease in the ventro-lateral columns. 



(11) The decrease of the " dorsal horns " is relatively less than that of the 

 cord and of any other part of the same. 



The rate of increase or decrease of the section area of the cord, of the grey 



