Material. Seeds of beans, peas, corn, canna, honey locust, and field beans.

Apparatus. Scale, 250-cc. graduated cylinder, 100-cc. wide-mouthed bottles.

1. To determine volume. Partly fill the graduated cylinder with water and read the height to which the column of water stands. Now count out fifty seeds of the bean, pea, and corn and drop each lot separately into the water in the cylinder. Remove the air bubbles each time by slightly shaking the cylinder. The height of the column of water is again read and the difference in the two readings indicates the volume of each sample in cubic centimeters. How does this vary with the different seeds? Explain.

2. To determine the amount of water absorbed by seeds. Weigh fifty seeds of peas, beans, and corn and tabulate the weight of each lot. Place the seeds in a wide-mouthed bottle of about 100 cc. and cover them with water. Allow them to stand for twenty-four hours in a room where the temperature is about 70° F. The following day remove the seeds, wipe dry, and weigh. Tabulate your results. Discuss. Allow the same seeds to soak in water for another day and note whether there has been any increase in weight. At what time was the greatest amount of water taken up? Discuss.

3. Now take fifty more seeds, the same as in 2, and treat in the same manner, only place them in a temperature of about 40° F. Note your results and explain.

4. Secure fifty seeds of the canna or honey locust and treat them in the same manner as in 1 and 2. Note the difference, if any, and discuss. How do you account for the change?

5. Weigh out two samples of field beans and place one lot in water and the second sample in damp sand. Weigh each lot the two following days and compute the per cent of water absorbed by each.

6. Weigh out two samples of field beans and place one sample in loose, moist sand and the other in the same kind of sand, but well packed and pressed over the seed. Weigh the seeds the two following days. Discuss and give your reason for the results obtained.

Reference

Goff, "Principles of Plant Culture," pp. 22-25.