Materials in Evergreen Herbaceous Leaves . 209 
It has been recorded earlier in the paper that material fresh from out- 
side responded to the general enzyme test. Experiment of January 9 in 
Table V shows that the enzyme in fresh material is not lipase — hence the 
presence of another enzyme is suggested. Owing to the browning of the 
leaf extract on standing, oxidases were suggested. 
It was determined ( 3 ) that guaiacum resin without the hydrogen peroxide 
was a test for oxidase alone, and so the material was subjected to this test. 
Sections of the leaves, both fresh and converting, gave only slight reactions 
with the guiacum resin, but the extract gave a good response. This is due 
to the fact that, on standing, a substance is formed in the extract which 
increases the oxidation ( 5 ). 
In the tests for lipase given above it will be noticed that phenolphthalein 
was used as an indicator instead of the litmus solution used by Reynolds 
Green in his experiments with extract from endosperms of Ricinus. Litmus 
was used in the early experiments in this work, but it was found that the 
plant extract decolorized the litmus directly it was added. This fact was 
a further proof of the presence of oxidases, as they cause an immediate 
decolorization of litmus solution. Hence litmus was of no use as an 
indicator in the presence of oxidases, and so phenolphthalein was substituted, 
with whose action they do not seem to interfere. 
The results of this investigation may be briefly summarized as follows : 
1. Most evergreen plants are destarch ified in NVV. Canada as early as 
October, and then contain a large amount of oil. 
2. Exposure to higher temperature in the case of Linnaea induces the 
formation of starch in darkness. 
3. Starch is present in the material after two days and increases in 
amount until about the eighth day. 
4. The starch is in a very finely divided state and the individual grains 
exhibit Brownian movement. 
5. All healthy leaves are capable of carrying on conversion. The plant 
does not possess ‘ starch 1 leaves and ‘ fat ’ leaves. 
6. The starch disappears when again exposed to moderately low 
temperature for about eight days, but the leaves are killed if exposed to 
extremely low temperatures when filled with starch. 
7. A decrease in the oil content is evident in leaves which have formed 
starch by conversion. 
8. Enzymes are present in material undergoing conversion. 
9. Lipase has been demonstrated in material undergoing conversion. 
10. Oxidases are present in the leaf of Linnaea even at quite low 
temperature. 
