1905.] On Reciprocal Innervation of Antagonistic Muscles. 279 
so in many instances—if the inhibiting stimulus is discontinued before the 
discontinuance of the stimulus inducing the reflex contraction (figs. 3 and 4). 
In the latter case, namely, that of inhibition of reflex “ after-discharge,” the 
reflex contraction is often permanently cut short (fig. 5). The inhibitory effect 
differs markedly from the effect of mere cessation of the stimulus exciting 
the reflex contraction (figs. 3, 4, 5, and 6). It acts more quickly, and, if 
strong, it relaxes the antagonistic muscle to a greater extent than does mere 
cessation of the stimulus exciting the active contraction. It depresses not 

Fie. 5.—Myograph record of reflex contraction of semimembranosus induced by stimulation 
(unipolar faradisation) of the skin of the homonymous foot. The duration of this 
stimulus is marked by the upper signal. The lower signal marks the time of 
application of a stimulation (unipolar faradisation) of the skin of the contralateral 
foot: this stimulation caused immediate relaxation of the contracting hamstring 
muscle, but the relaxation did not proceed beyond a certain grade. Time is marked 
above in fifths of seconds. 
only the active reflex contraction, but the degree of reflex tonus of the muscle 
on which the active reflex contraction was superadded (fig. 3, and the right 
hand example in fig. 6). It relaxes the muscle even down, as was said in a 
previous Note, to its post-mortem length. 
It is interesting that this inhibition of reciprocal innervation is seen in 
many occasions to steady a muscle which under experimental interference 
with the muscles and nerves of the part is exhibiting tremor and twitchings. 
This effect is seen in fig. 7, where the semitendinosus muscle during the course 
of an experiment on the nerves of the hind limb of a dog, the spinal cord of 
