92 JOURNAL OF COMPARATIVE NEUROLOGY. 
Chart I 
A.—— Male. Kolliker. 
Be as von Wi qle 6 Ing bert. 
C.———— Female. Stilling. 
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Slee ae ene, 
Kolliker. 
Inéb ert. 
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ITTV VY UWWInM VY v Wo vt Wl K X M XT I 0 mwvinmre 
CERVICAL THORACIC LUMBAR SACRAL 
Fig. 1 
Chart I. Curves showing the areas in sq. mm. of the cross-sections of the 
dorsal roots of the left spinal nerves. Each sq. mm. is represented by 20 divi- 
sions on the axis of ordinates. 
Chart JJ. Curves based on the measurements used in Chart I; the values 
in each curve being entered in percentages of the greatest area, which is taken 
as 100%. One mm. on the axis of ordinates equals 1%. 
Chart /I1. Curves showing in percent. the areas of the cross-sections of 
the dorsal roots of the left spinal nerves (Author), and the percentage distribu- 
tion of the number of medullated nerve fibers in each dorsal root. (Author). 
The close concordance between these two curves is a matter of interest as well 
as of importance, as it shows that there is a close relation between the size of a 
root and the number of nerve fibers in it. The divergence in the Lumbar 
region I take to be due to the compactness of these roots at the places where 
they were sectioned. 
The depression in the curve above C. IV is also a fact worth noticing, 
whatever may be its significance. 
