The Motor Ganijlioji Cells of the Fray's Spinal Cord. 79 



It remains to briefly consider the relation of the fibres and 

 cells of different regions. 



TABLE XXI. 



Frog No 



Fibres, Nerves 1-3 , 



Cells of brachial region 



Difference 



Fibres, Nerves 4-10 



Cells of dorso-lumbar region. 

 Difference , 



The table shows that we have too many cells in the dorso- 

 lumbar region, too few in the brachial. The latter must 

 therefore draw on the former, and, as already remarked, 

 there are ascending fibres from the middle region of the 

 cord. 



We can also determine the point where the supply for the 

 lumbar plexus begins. 



The first six nerves contain in Frog 36, 5236 fibres, in 43, 

 7040. In figures II and III this point is marked with d, a 

 point in the middle region just above the lumbar enlarge- 

 ment. This confirms previously advanced views. 



IV. NuMBEK OF Sensory Fibres. 



The following table gives the facts so far as I have invest- 

 igated them. 



Table XXII. 



