Fig. 1. 
In many cases of undoubted exaggeration of the knee-jerk we 
also find very nearly 0.20 second. Fig. 1 shows such a curve in 
which the time marks, as in all the other curves in this paper 
represent 0.1 second. This record mnst be considered as an instance 
of the simplest form of an exaggerated deep reflex. I can add that 
this simplest form is rather a rare one and that more complicated 
forms are more usually met with. All the more complicated forms 
are characterised by the occurrence of more than one top in the 
graphical record. Amongst these we must consider in the first place 
the simple clonic reflex, where the simple twitch is entirely absent 
and replaced by a small series of clonic contractions (fig. 2). These 
bren Erben Een nn nen 
Fig 2. 
are generally rather limited in number and we find perhaps only 
47 contractions in all. But in a few cases quite a long series of 
clonic contractions may be seen (fig. 3). Curves of this kind may be 
found in patients where the mechanical and physiological conditions 
for permanent clonus are present. This means that the reflex irrita- 
bility as well as the muscle tonus are greatly increased; also that 
the leg of the patient must be kept in such a position that nothing prevents 
the occurrence of clonus. Clinically we can find this in patients 
with organic as well as functional diseases of the nervous system. 
In functional disorders even the tonic rigidity of the muscles need not 
be present as a state of active muscle contraction may provide the 
mechanical condition for a clonus as well as a tonic spasm does. 
