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of caustic potash and 173 grams of sodium-potassium-tartrate (Rochelle salt) in 500 c.c. of water, and label " Solution B." When required for use mix equal quantities of A and B (only a small quantity, sufficient for immediate use, should be mixed each time). (5.) Place some glucose (grapesugar) in a test-tube, dissolve in water, add a few drops of Fehling's solution, and then boil. A red deposit of cuprous oxide will be precipitated. (6.) Dissolve a few grains of cane-sugar in water, and test as in the last experiment. No precipitate will be formed if the cane-sugar is free from glucose. (7.) Conversion of cane-sugar into glucose: Make a solution of cane-sugar, and add to it a few drops of hydrochloric acid. Boil the liquid well, and then neutralise the acid with a weak solution of caustic potash or sodium-carbonate. Add Fehling's solution and boil again. Notice whether a red precipitate is formed. (8.) Conversion of starch into sugar by action of diastase: Having prepared some very thin starch paste, pour it when cool into three test-tubes, a, b, and c. To a add a few drops of iodine-solution, to show the presence of starch ; to b and c add equal quantities of diastase-solution (made by dissolving a few grains of prepared diastase, obtainable from a chemist, in water). Test for the presence of starch in bby taking out small quantities at intervals of five minutes and adding iodine in a series of test-tubes. When b no longer shows traces of starch, test c for sugar with Fehling's solution. (Note: If prepared diastase is not procurable, add 5 gr. of malt to 50 c.c. of cold water ; allow to stand for four hours : then filter.) (9.) Diastase in young seedlings: Pound up in a mortar about fifty 7 j 7 oung germinating barley seedlings. Make a weak starch paste, as in the last experiment, add a tablespoonful to the barley-plants. Leave in the dark, and test with iodine at intervals of a few hours, noting the gradual disappearance of the starch as it becomes converted into sugar. Structure and Germination of Seeds.—(l.) Soak a pea or bean seed and a grain of wheat or maize in water for twenty-four hours. Notice in the former the testa, or outside covering, the embryo, consisting of radicle and plumule, and the two cotyledons. In the latter notice the embryo, with one cotyledon, the separate store of food (endosperm), and the scutellum, separating the embryo from the stored food. (2.) Notice the changed appearance of the seed-coats of beanseeds after soaking for a short time. Absorption of Moisture by Seeds: —(3.) Take a number of liean-seeds, and paint half of them with enamel paint on the edge where the hilum (scar) and micropyle (small opening) are situated. Coat the rest of the beans with paint, so as to leave only these parts exposed. Weigh the two sets of beans separately, soak in water for some hours, and then weigh again, observing which set has absorbed more moisture. (4.) Soak and examine a number of different kinds of seeds, noting whether they contain one or two seed-leaves, and whether they have a separate store of food, as the wheat and maize have. (5.) Prepare a seed-bed, either in a box or in the garden, and sow in it as many different kinds of seeds as possible. Sow one or more seeds of each kind every 7 two days, and when the last seed is well above ground pull up the whole set, examine the seeds and plants, and make drawings. Observe especially how the young plant emerges from the soil, the curves assumed by the stem, how the plant gets rid of the seedcoat, and any means provided for holding down the seed-coat while the leaves are being withdrawn. The following seeds are suggested for study: Pea, beans (various), cabbage, radish, marrow, pumpkin, oak, buckwheat, barley, wheat, maize, onion, castor-oil, date, nikau, and seeds of native forest-trees when obtainable. (6.) Conditions necessary for germination: Place some barley 7 -seeds (a.) in a dry saucer in a warm place ; (b) in a moist earthenware vessel, or on damp flannel in a warm place, exposed to light; (c) as in (b), but protected from light, allowing, however, free access of air ; (d) in a bottle of previously boiled water, tightly corked, and placed in the dark ; (c) as in (c), but in a cold place. After a few days compare the results. (7.) Production of carbon-dioxide during germination : Allow seeds to germinate in a closed bottle, and then test the gas in the bottle (17) by introducing a lighted taper, (b) by means of lime-water. Is there any alteration in the appearance of the seeds as the plants grow? (8.) Increase in temperature during germination : Fill a beaker with moistened seeds and another with moistened sand. Place a thermometer in each so that the bulb is well covered, and allow the vessels to stand side by side in a warm situation, noting any difference in temperature. (9.) Increase in size of seeds when moistened : Fill a common bottle with pea, bean, or barley seeds, pack tightly, add water enough to moisten them, and cork the bottle securely. Put the bottle in a warm place, and cover with a box. (10.) Changes in stored food during germination : Notice the difference in taste between germinated and ungerminated barley-seeds. (11.) Dry crushed barley and malt in an oven; weigh out equal quantities of each, and then add twenty times their weight of water. The mixtures should be left for several hours, shaken at intervals, and then filtered, after which the residues should be dried and their weights compared. What causes the difference in weight? (12.) Testing vitality of seeds: Take an equal number of new, one-year-old, and two-year-old seeds of the same kind, and place them between damp flannel in earthenware saucers to germinate. Inspect the saucers day by day, removing germinated seeds, and at the end of two weeks calculate the percentage of germinating seeds in each sample. (13.) Test samples of various commercial seeds as in the preceding experiment, and ascertain the proportion of good seeds. (14.) Depth at which seeds germinate best : In a box of prepared soil sow pea, bean, oat, or other seeds at various depths. Provide suitable conditions for germination, and note the dates on which the plants appear, and their comparative vigour. (15.) Dispersal of seeds: Make a collection of seeds and fruits, which may be mounted on cards, classifying them in the following manner: (a) Seeds dispersed by expulsive mechanism (e.g., gorse, 'balsam, broom, <fee): (b) seeds and fruits which creep or hop along the ground (e.g., fruits of some grasses, seeds of some scabiouses): (c) seeds and fruits carried by the wind —(1) those provided with wings (e.g., elm, pine, sycamore, birch, parsnip, ash) ; (2) those which have feathery parachutes or pappi (e.g., dandelion,"thistle) : (d) seeds of berries and fleshy fruits, carried bybirds (e.g., cherries, blackberries, raspberries): (c) seeds and fruits bearing hooks or spines (e.g.. burr, Uncinia, &.c): (f) seeds of sticky fruits (e.g., Salvia, mapau (Pittoeporum): (g) fruits and seeds carried by water (e.g., cocoanut and other tropical fruits and seeds; seeds of aquatic plants, such as water-lily).