( 552 ) 
The determinations always took place in the same way. The minced 
muscles were for some hours at a stretch boiled in 0.1 % HC1, in 
consequence of which the tissue breaks altogether and all the creatine 
passes into the liquid. By evaporation the extract after being freed from 
protein, was concentrated and then with then double volume of normal 
HC1 heated to 115° C. in the autoclave for half an hour, by which 
the creatine is completely changed into creatinine. Then the determi¬ 
nation took place, according to the method of Folin, with the colori¬ 
meter formerly shown in the meeting of this Academy. 
First of all we have some observations to mention about decrease 
of the quantity of creatine in muscles, of which the tonus, in conse¬ 
quence of section of the nerve, was eliminated. In the outset we 
came to very irregular results when examining the muscles of the 
hindlegs of rabbits and of a young dog, after a one-sided cutting of 
the nervus ischiadieus. Now less creatine was found in the muscles 
of the paralyzed leg, now more creatine in those of the paralyzed 
side. The cause of this irregularity appeared to be that we did not 
compare exactly corresponding muscles. Especially in the rabbit the 
difference in quantity of creaane in white and red muscles is rather 
considerable. With 10 rabbits we found in the gastrocnemius on an 
average 4.463, in red muscles (soleus, semitendinosus and semimem¬ 
branosus examined together) 2.925 mgr. creatinine in 1 grm. of the 
muscle. 
When this source of error was avoided, the influence of section 
of the ischiadieus became clear. With 3 rabbits we have, taking 
into consideration what has been said above, repeated the experiment 
and three days after the section of the nervus ischiadieus, we have 
examined the gastrocnemius of the paralyzed and of the not paralyzed 
leg. We found: 
Not paralyzed. Paralyzed. Loss after paralyzing. 
I 4.703 4.232 0.471 mgr. cr. p. gr. of the muscle 
II 4.448 4.289 0.159 „ „ „ „ „ „ 
III 4.983 4.013 0.970 „ „ ., „ „ „ 
Although the differences found lie without any doubt beyond the 
limits of the errors of observation, yet we have not continued these 
experiments, because too little can with certainty be concluded from 
them concerning the influence of the tonus. It is true, the muscles of 
the leg the ischiadieus of which has been cut through, are distin¬ 
guished from those of the other side by the loss of tonus, but there 
are also other differences, which are perhaps of importance, as Weber 
has already observed, who also found the quantity of creatine in 
