488 AMERICAN JOURNAL OF BOTANY [Vol. 8, 



hydrolyzed with HC1 and then neutralized with NaOH, it reduced the 

 Fehling'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 



i. Apple — 10. Pine, Austrian — 



2. Corn + II. Pine, white — 



3. Daisy — 12. Ragweed — 



4. Dandelion — 13- R ye + 



5. Dock + 14. Timothy + 



6. Elm + 15. Magnolia - 



7. Goldenrod — 16. Maple, Norway — 



8. Lily, Easter — 17. Lilium riibrum — 



q. 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 \ hour 

 to 1 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 



