t 554 ) 
leg got into tonus, the left one remaining slack. Sometimes, in order to 
strengthen the tonus in the foreleg, also the spinal cord, at about 
the eleventh breast-vertebra, was cut through. When the tonus had 
lasted a few hours, the animal was killed by suffocation. Directly 
after the triceps braehii on both sides was prepared, minced and put 
into hydrochloric acid. 
In all experiments we found the muscle that had been in tonus, 
richer in creatine than the one that had-remained slack, and that, 
expressed in mgr. creatinine on 1 grm. muscle, as follows : 
Tonus Slack Difference 
I 3.690 3.090 0.600 
II 4.340 3.848 0.492 
III 4.291 3.902 0.317 
IV 3.806 3.185 0.621 
V 3.198 2.963 0.235 
It is remarkable that this difference pretty \yell keeps pace with 
the difference that in the experiment of the contraction of the muscles, 
right and left, was observed. In experiment I and still more in IV, 
the stiffness on the right was very beautifully developed, in II the 
tonus was strong, but of a shorter duration, in III the tonus on the 
right was good, but also the left foreleg occasionally showed some 
stiffness, which also occurred in V, though in a smaller degree, 
whilst the stiffness developed here slowly and to not so high a 
degree as otherwise. 
We think we are entitled to derive from these experiments that 
by the muscles in tonus more creatine is formed than by those 
which are slackened. For the supposition that the difference may be 
attributed to an increased decomposition of creatine in the slackened 
muscles, it seems that there is not a single ground to be adduced. 
Besides this we have made a number of experiments with frogs 
(Rana esculenta). 
In the first place the influence of irritation with induction-currents 
on the quantity of creatine in muscles was examined. About this 
communications have been made by Mellanby and by Graham 
Brown and Cathcart* *}. By direct irritation Mellanby brought the 
muscles in tetanus and then he found so slight an increase of the 
quantity of creatine that he came to the result: “that the perfor- 
b Journ. of Physiol. Vol. XXXVI, p. 447. 
*i Bio-Chemical Journ. Vol. IV, p. 420. 
