1893.] 



of the Sympathetic Nervous System. 



555 



Skin 



FIG. 1 is a diagram of the course of the pilo-motor and sensory fibres to the skin 

 near the mid-dorsal line, when the 6th grey ramus contains no pilo-motor 

 fibres. The thick lines represent the sensory spinal fibres; the thin lines 

 accompanying them the sympathetic fibres. The arrow represents a line of 

 skin at about the end of the sacrum. 



Skin 



IV 



FIG. 2 is a diagram similar to that of fig. 1, but for the case when the 5th, 6th, 

 and 7th grey rami have no pilo-motor nerves. The shifting which commonly 

 occurs of some fibres of the 4th lumbar into the 3rd, and of some fibres of the 

 1st sacral into the 2nd, is here left out of account. 



