I 20 
Vines — The Proteases of Plants {IV). 
breaking up on the seventh day, and had disappeared on the eighth. Thus 
it was found that the mixtures of the ungerminated seeds of the Pea, the 
Lupin, and the Maize, gradually acquired, under experimental conditions, 
the capacity for digesting fibrin. I cannot explain why this capacity was 
not equally developed in Vicia Fab a, Phaseolus multiflorus , and Phaseolus 
vulgaris : I can only suggest that in these cases the process is slower, and 
that possibly fibrin-digestion might have been observed had the experiments 
been more prolonged. 
The probability of the suggestion made in connexion with the 
experiments on germinated seeds, that two proteases are active during 
germination, is materially increased by these experiments on ungerminated 
seeds. It is not reasonable to attribute the digestion of the fibrin, which 
took place five to ten days after the experiment had begun, to the protease 
in the resting seed that was found to digest Witte-peptone within a few 
hours : for if this protease were capable of digesting fibrin, why was its 
action so long delayed ? It is more in accordance with the observed facts 
to conclude that the ungerminated seeds contained, to begin with, an 
ereptase but no protease capable of digesting fibrin ; and that, in certain 
cases, such a protease was gradually developed in the course of the 
experiment. 
It occurred to me that it might be possible to accelerate the fibrin- 
digestion by chemical means ; and, with this object in view, I made some 
experiments in which the distilled water was replaced in the mixtures by 
NaCl-solutions. The attempt did not prove successful, but the experiments 
are nevertheless worth mentioning. In the first set, 5 °/ o NaCl-solution 
was used : the result was that in most cases ( Vicia Faba , Phaseolus 
vulgaris , Pea, Lupin) the fibrin completely disappeared within 72 
hours. This seemed to be satisfactory, but there was the possibility that 
it might be due, wholly or in part, to solvent action of the salt ; and, 
as a matter of fact, it was found, in a control-experiment, that 0-3 grm. 
fibrin was completely disintegrated, though not altogether dissolved, 
when digested for three days in 100 c.c. 5 °/ o NaCl-solution alone, with o-i °/ o 
HCN. In a second set of experiments, a 2-5 °/ o NaCl-solution was 
used, with the result that the fibrin disappeared in about ten days in the 
case of the Pea and of the Lupin, but not in any of the Beans (the Maize 
was not tried), a result which is much the same as that obtained when 
distilled water was used. It may be added that digestion of 0-3 grm. fibrin 
with distilled water only, containing o-i °/ o HCN, produced no effect 
though continued for more than a fortnight. 
