1905] DEAN—PROTEOLYTIC ENZYMES 127 
Samples of preparations C, D, and E were finely ground, dried to 
constant weight and estimations of the coaguable and non-coaguable 
nitrogen were made in the same way as the similar determinations on 
A and B. 
Total nitrogen in 18™ of C - - - - - oe a eee 
Total nitrogen in 12™ of D - - - - - -o 0.0426 
Total nitrogen in r2™ of E - oe - - 4. 15s ae ae 
Percentage of nitrogen in C as coaguable proteids ~~ ee eo 
Percentage of nitrogen in D as coaguable proteids : ae 
Percentage of nitrogen in E as coaguable proteids - - - 79.9 
Percentage of non-proteid nitrogen in C_~ - - - - - - 18.3 
Percentage of non-proteid nitrogen in D - - - #2 oe 12.0 
Percentage of non-proteid nitogn in A  « . -. - £55 ee 
These results would indicate that under the conditions of the 
experiment there is no proteolysis occurring, although, as previously. 
stated, the cotyledons still contain ereptase. A small increase in 
Coaguable nitrogen was observed, followed by a rise to about the 
original amount. There seems to be no evident explanation for these 
small variations. Two facts may be noted: the oxygen supply to the 
living cells in the interior of the cotyledons was probably curtailed by 
the presence of the layers of dead cells on the surface; the correlation 
of the parts of the organism had been destroyed and the influence of 
that factor on the metabolic processes is not known. The results 
tend to emphasize the dependence of proteolysis in this seed upon 
the normal life of the organs. 
DISTRIBUTION OF THE PROTEASES IN VARIOUS PARTS OF PLANTS OF 
PHASEOLUS VULGARIS : 
A large number of qualitative tests for proteolytic enzymes in 
Various parts of the plants of Phaseolus were carried out, using the 
tryptophan reaction as an indication of proteolysis. It scems 
scarcely necessary to detail the methods and results in every instance. 
“he €xperiments were conducted in a way anzlogus to those on the 
cotyledons in the various sta ges of germination, a full description of 
Which was given in a former paper. In testing for a tryptic enzyme 
the tissues Were sometimes allowed to autolyze without the addition 
of any further proteid, but in most cases edestin, phaseolin, or unco- 
agulated gg albumin was added. In searching for evidence of 
