2. Grow various plants, e.g. Tropæolum, Geranium, Fuchsia, Mustard, etc., in the window, and notice the effect which the direction of the light has upon the positions of the leaves.
3. Smear with vaseline the lower surfaces of various growing leaves, and on the following day test the leaves for starch, comparing each with an unsmeared leaf from the same plant.
4. How is the transpiration of water from a green leaf effected and controlled? Discuss the uses of transpiration. (1897)
5. Put the same quantity of water into each of two similar test-tubes, and let the end of a leafy twig dip into one. Weigh the tubes, place them together in the sun for an hour, weigh again, and estimate roughly the weight of water lost by one square inch of leaf surface per hour. Compare various plants in this respect. Repeat the experiments, (a) in a moderate light, (b) in the dark.
6. Make a list of plants in which the leaves are so arranged as (a) to conduct rain-water towards the base of the main stem, (b) to cause rain-water to fall to the ground from the outside of the foliage. Try to discover whether the difference has any relation to the arrangement of the roots.
7. Under what conditions can plants use carbon dioxide as a source of food? Mention experimental and other proofs of the principal statements made. (1905)
8. What part of its food does a green plant obtain from the air? In what form and under what conditions is it taken in? (King’s Scholarship, 1905)