Vines, — Proteolytic Enzymes in Plants. 251 
previously been boiled ; to No. 3, 0-3 grm. of Witte-peptone was 
added. 
After 22 hours’ digestion, No. 1 gave a distinct tryptophane-reaction ; 
No. 2 no reaction ; No. 3 a marked reaction. 
Precisely similar results were obtained with the Hyacinth ( Hyacin - 
thus orientalis), and with the Onion ( Allium Cepa) : the expressed 
juice of the onion gives a marked tryptophane-reaction. 
Tubers. 
Solarium tuberosum . 
5 grms. of the cortical tissue of a potato were placed in each, of two 
bottles, 1 and 2, that in 2 having been previously boiled : to each 
0-3 grm. of Witte-peptone was added, and both were filled up with 
chloroform-water (about 50 cc.). After 24 hours’ digestion, No. 1 
gave distinct tryptophane-reaction, No. 2 no reaction. 
Similar results were obtained with the tuber of the Jerusalem 
Artichoke (. Helianthus tuber osus). 
Roots. 
Experiments were made with the roots of the Tomato, the 
Vegetable Marrow, and the Scarlet Runner : as also with 
the tuberous roots of the Turnip, the Carrot, the Beet, and 
Mirabilis Jalapa . 
Brassica Rapa. 
The expressed juice of the turnip gives distinct tryptophane- 
reaction. 
30 cc. of the juice were placed in each of two bottles: to No. 1, 
nothing was added; to No. 2, 0-3 grm. of Witte-peptone and 1-5 cc. 
of 4 % HCN (= o*i8 %). 
After 7 hours’ digestion, No. 1 gave the same tryptophane-reaction 
as at first, No. 2 gave a strong reaction. 
Similar results were obtained with the other roots, either the bruised 
root or a watery extract being used. 
I have so far obtained evidence of the proteolysis of Witte- 
peptone by all the vegetable substances employed, with the 
exception of the pulp and juice of the Apple and of the 
Orange. Proteolysis seems to be effected almost equally 
well when the reaction of the liquids is alkaline (0-5 °/ o 
