THE ROOTS OF THE PERIPHERAL NERVES, ETC. 



glion in two directions, 

 and that fibres which 

 originate in the spinal 

 cord only pass through 

 it. We may, therefore, 

 consider the relations of 

 the sensory roots to the 

 spinal ganglia to be as 

 represented in the dia- 

 gram, Fig. 88. 



Between the spinal 

 ganglion and the cord 

 the sensory and motor 

 roots divide into a num- 

 ber of root-fibres, which 

 for some considerable 

 distance enter the spinal 

 cord, the sensory fibres 

 on the dorsal aspect, 

 and the motor fibres on 

 the ventral surface, in 

 a groove situated some- 

 what laterally. The 

 number of these root- 

 fibres is not alike for 

 all roots, and differs in 

 different individuals. 



Recent investiga- 

 tions show that each 

 root does not corre- 

 spond to one definite 

 peripheral nerve. It has 

 been proved that in 

 each peripheral nerve 

 there is contained a 

 large number of nerve- 

 fibres from different 

 roots, and it is very 



