348 
Proceedings of the Royal Society of Edinburgh. [Sess. 
of certain polypeptids, it follows that it may he used for measuring the 
activity of all enzymatic preparations which are capable of catalysing this 
reaction. Abderhalden has demonstrated the presence of such enzymes in 
numerous cases in both animal and plant tissues, such as kidney, lung, 
intestine, various fungi, etc. ( Zeitschrift fur physiologisches Ghemie, lxv. 
p. 180; lxvi. pp. 137 and 276; lxviii. p. 312). I have myself tried the 
method for testing the activity of the peptolytic enzyme in yeast with good 
results, and am now testing the applicability in the case of seed enzymes. 
It further follows that peptolytic enzymes which are incapable of 
catalysing this reaction, and for which the method can accordingly not be 
used, must be of an entirely different nature from that produced by the 
pancreas. 
{Issued separately April 12 , 1911 .) 
