264 Mr. Graham Brown and Prof. C. S. Sherrington. [Mar. 16, 



the action of an F point is reversed after stimulation of an E point, and 

 probably in consequence of the action of that point. This is shewn in the 

 accompanying figure (fig. 11). Here the F point, although it caused contrac- 

 tion of the flexor four seconds before the stimulation of the E point, produces 

 four seconds after that stimulation nothing but relaxation of that muscle, 



Fig. 10. 



Fig. 11. 



Experiment 14, Macacus sinicuS, 21.2.12. E.F.E. — This record demonstrates the same 

 phenomena of reversal as the preceding one, but the appearances are more complete. 

 Here the first E stimulus evokes extensor contraction and flexor relaxation. The second 

 E stimulus (applied after a flexion-point stimulus) gives flexor contraction and slight 

 extensor relaxation— a clear case of complete reversal. 



Experiment 14, Macacus sinicus, 21.2.12. F.E.F.F.— In this record an F stimulus 

 (C— D, I) gives a good flexion reaction. An E stimulus (E— F) then gives a reaction in 

 which there is exhibited at first augmentation of flexor tonus and then flexor relaxation 

 accompanied by extensor contraction. A second F stimulus (C— D, II) then gives a 

 relaxation of the flexor contraction in an epileptic state, as also does a third. 



