488 
AMERICAN JOURNAL OF BOTANY 
[Vol. 8, 
hydrolyzed with HCl and then neutralized with NaOH, it reduced the 
Fehhng's solution, indicating the presence of a sucrose. 
Tests for Starch 
Solutions were treated first with chloral hydrate to render the grains 
transparent, and afterwards with iodine. 
Table i i . Tests for Starch in Different Kinds of Pollen 
1. Apple — 10. Pine, Austrian — 
2. Corn + II. Pine, white — 
3. Daisy — 12. Ragweed — 
4. Dandelion — 13. Rye + 
5. Dock + 14. Timothy + 
6. Elm '. . . + 15. Magnolia — 
7. Goldenrod — 16. Maple, Norway — 
8. Lily, Easter — 17. Lilium rubrum — 
9. Lily, tiger — 18. Maple, red — 
Tests for Zymase 
The different kinds of pollen were tested with Pasteur's fluid, in Smith's 
fermentation tubes, for zymase. Toluol was added to inhibit bacterial 
action or molds. Apple pollen was the only one which showed any reaction, 
and since this was after standing 48 hours the result was doubtful. Since, 
however, apple pollen has been an exception in other instances, this test 
will be repeated when more pollen is available. 
Tests for Invertase 
Equal amounts of the different kinds of ground pollen (about 150 mg.) 
were added to 5 cc. of 3 percent cane sugar solution with 5 cc. of distilled 
water and 8 drops of toluol. Equal amounts of ground pollen were boiled 
with 5 cc. of distilled water and added to 5 cc. of the cane sugar with 8 drops 
of toluol solution for controls. The two sets of tubes were allowed to stand 
for 24 hours in a warm room. Then to 15 drops of each pollen solution 
were added 15 drops of Fehling's solution and the tubes were heated J hour 
to I hour in a boiling water bath, and the rate and amount of reduction 
in the different tubes were observed. Although this was not an exact 
quantitative test, as for the Easter lily pollen, yet the varying amounts of 
reduction in the different pollen solutions, and the differences between the 
active solutions and the controls, were strikingly noticeable. When the 
pollen was acid, producing a green color in Fehling's solution before heating, 
the tests were repeated, neutralizing the solution first. This was marked 
in red maple. Since the active pollen in every case caused more reduction 
than the boiled control, the reduction could not have been due merely to 
the reducing sugars of the pollen grains since the ruptured boiled grains 
would have yielded just as much sugar. The difference, therefore, may be 
