336 BOTANICAL GAZETTE [way 
these differences cannot be held to show the presence of a trypsin- 
like enzyme, especially when we see the change in the digestion 
containing Witte peptone which at first required 1.4°° of acid for 
10°° of filtrate and at the close 6.5°°. 
Being convinced by the experiments tried that the resting and 
germinating bean contained an ereptase, I attempted to separate 
it from the mass of other materials in the seed extracts. 
One hundred and fifty grams of bean meal were extracted for 
five hours with 375°° of water with the addition of toluol and chloro- 
form. The fluid was strained and pressed out through cheese cloth, 
the residue mixed with 150°° of water and this likewise removed. 
The total extract, amounting to 450°°, was allowed to settle over night 
to get rid of the starch, etc. by sedimentation. The next morning 
the supernatant fluid was siphoned off and filtered three times through 
pulp filters, yielding 365°° of an opalescent fluid. This was half 
saturated with ammonium sulphate by adding an equal volume of 
saturated ammonium sulphate solution. The flocculent precipitate 
A was removed by filtration, and to the filtrate saturated ammonium 
sulphate solution was added to make two-thirds saturation. Pre- 
cipitate B was likewise removed and ammonium sulphate added to 
three-quarters saturation. With this concentration of the salt nothing 
but a turbidity resulted; accordingly ammonium sulphate in substance 
was added to saturation, yielding the precipitate C. A small portion 
of each precipitate was placed in a test tube and mixed with Witte 
peptone and water; after standing over night in the incubator the 
fluids were tested for tryptophan. The results showed that A con- 
tained sufficient ereptase to cause a strong tryptophan reaction, B 
a weak one, and C none at all. Each precipitate was dissolved in 
water so far as possible, and the turbid solution placed in dialyzing 
bags and dialyzed until practically free from sulphates. In A a 
considerable amount of phaseolin was precipitated on the sides of the 
‘dialysis; this was filtered off, washed with water, and both the clear 
filtrate and the globulin tested with Witte peptone. It was found 
that the ereptase had remained in solution and had not been carried 
down with the precipitated proteid. The solutions of the precipitates 
Band C, after dialysis, were found to have respectively a weak action 
on Witte peptone and no action at all. 
