DonaLpson AND Davis, Human Spinal Cord. 27 
TABLE V. 
Giving in cubic millimeters the volume of the gray substance in each 
segment of the mature human spinal cord. With the exception 
of the first cervical segment, the volume is obtained by multiply- 
ing one-half the sum of two limiting ordinates by the length of 
the intervening segment, based on the data used for the composite 
curve in Chart I. 
Volume in Volume in 
Segment cubic mm. cubic mm. 
Cervical I 129 
II 157 
III 178 
IV 220 ) 
AG 224 | Cervical segments IV-VIII 
VI 275 1220 
VII 261 [ 
VIII 240 J 
Thoracic I 177 
Il 147 
Ill 14! 
IV 148 
Vv 171 
VI 198 
VII 180 
Vill 159 
1X 156 
Xx 169 
XI 178 
XII 187 
Lumbar I 216 ) 
II 184 | Lumbar segments I-V. 
III 228 $ 1086 
1V 256 
Vv 202 | 
Sacral I 192 
II 176 
Ill 105 
IV 67 
Vv 34 
‘Coccygeal iT 12 
An examination of the foregoing Table V shows some re- 
lations worthy of remark. In the first place, the greatest vol- 
ume of gray substance is here found in the segment C VI. In 
the last five of the cervical segments, the total volume of gray 
substance is 1220 cubic millimeters, being thus decidedly 
greater than the volume of substance in the five lumbar seg- 
ments, which contain but 1086 cubic millimeters. 
