A DESCRIPTION OF CHARTS SHOWING THE AREAS 
OF THE CROSS SECTIONS OF THE HUMAN 
SPINAL CORD AT THE LEVEL OF EACH SPINAL 
NERVE. 
By Henry H. Donatpson anp Davip J. Davis. 
(From the Neurological Laboratory of the University of Chicago.) 
A. CURVES SHOWING THE AREA OF THE CROSS-SECTION OF EACH 
SEGMENT OF THE MATURE SPINAL CORD. 
Introduction. 
The data which are presented in this paper were gathered 
for the purpose of preparing a curve based on the human 
spinal cord, with which to compare the areas of white and gray 
substance found in the cross sections of the spinal cords of 
other mammals. Reference to the literature shows that 
with the exception of the curve presented by KrausE and 
AGUERRE (1), which was published while this study was in pro- 
gress, the series of curves appearing in the text-books and used 
to show the areas of the gray and white substance at different 
levels of the cord, was first introduced by WoroscuitorF (2), 
- while that investigator was making a study of the conduction 
paths in the spinal cord of the rabbit. _WoRoSCHILOFF’s curves 
were based on measurements published by B. STILLING (3). 
The fact that the records which WoroscHILOFF chose as 
‘the basis for his curves were froma child of five years, and 
therefore from acord not completely developed, has been re- 
cently pointed out by several writers. That WoroscHILOFF 
‘should: have used these particular records of STILLING, instead of 
» taking the records for mature cords, published in the same vol- 
