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Experiments with Roots.-—(1.) Roots of young plants; comparison between roots of monoand di-cotyledons: Examine young plants of pea, bean, barley, oats, &c, and observe the difference between the roots of plants with one seed-leaf and those with two. (2.) Root-hairs: Allow some barley or radish seeds to germinate on damp blotting-paper in a saucer, and examine the roots with a lens from time to time. Make sketches of several seedlings of different ages, showing the exact position of root-hairs. (3.) Root-caps: Suitable specimens for examination are —Aerial roots of screw-pine, pea and bean seedlings, roots of some water-plants (e.g., duckweed), as well as roots of cuttings grown in water. Hold delicate specimens up to the light and examine with a lens. (4.) Growth of roots: Notice the roots of a full-grown monocotyledonous plant, such as wheat, maize, or any grass Compare these with the branching roots of a dicotyledonous plant, such as a forest-tree, observing the increase in thickness of the main roots in the latter. (5.) Increase in length: On the root of a young bean-seedling make a number of marks in ink at regular intervals, making at the same time corresponding marks on a piece of card laid alongside. Now place the seedling in a damp atmosphere, root downwards, and allow it to grow. After a day or two again look at the plant, and ascertain the region of greatest growth by comparing the marks on the root with the marks on the card. The seed may conveniently be wrapped in moist cottonwool, and placed in v thistle funnel standing in a beaker, the root being allowed to grow down the tube. (6.) Primary and secondary roots: Slice the main roots of a broad-bean seedling, and notice where the secondary roots originate. Cut a longitudinal section of a carrot, and trace the roots through the "rind" to the "core." (7.) Influence of gravitation on roots: Place beanseeds, with roots about an inch long, in a damp atmosphere, allowing the roots to point in various directions. Examine the specimens from time to time, and note the direction taken by the tips of the roots. (8.) Influence of water on roots: Sow some peas in a sieve (or a conical bag of mosquito-netting suspended from a retort-stand ring) filled with damp sawdust. When the roots project through the meshes notice whether they grow downwards vertically or along the bottom of the sieve or bag. (9.) Behaviour of roots towards light: Grow an aquatic plant (e.g., watercress) in a tumbler of water, and place round the tumbler a mask of black paper with a slit in one side to admit light. Also cover the top of the tumbler with a card. Now place the vessel in a window, with the slit towards the light, and in a few days observe whether the roots have turned towards or away from the slit. (10.) Absorption by roots: Fill two small bottles with water, adding to one a few drops of red ink or cosine, and to the other a little carmine worked up into a paste. In each bottle place a young seedling, so that its roots are immersed in the water, securing the plants by packing the necks of the bottles with cotton-wool. After a few days wash the seedlings and cut them lengthwise and across, noticing which plant has become red inside, the one placed in the soluble cosine or that in the insoluble carmine. (11.) Over the ends of two thistle funnels tie tightly pieces of bladder. In one funnel place coloured water containing sugar in solution, and stand it bulb downwards in a beaker of water. Into the other funnel pour clean water, and stand it in a beaker containing sugar-solution. After a time observe whether the liquid in the funneltubes has risen or fallen. (I--) Action of roots on rocks: Allow seedlings to grow in sawdust or sand on a polished marble slab, so that their roots spread over its surface. After a couple of months have elapsed remove the plants and examine the surface of the slab. (Note: Tilt the slab slightly, and do not grow too many seedlings.) (13.) Exudation of acid by roots: Pull up some plants, and lay moist blue litmus paper on their roots. Experiments with Stems. —(1.) Gather and examine specimens of plants with the following types of stems: (a) Upright woody stems; (b) upright non-woody or herbaceous stems— e.g., sunflower, balsam, potato, grasses, &c. ; (c) stems of climbing plants— e.g., pea, Virginia creeper, ivy; (d) twining stems — e.g., convolvulus, hop, scarlet-runner; (c) creeping stems— e.g., couchgrass, verbena, strawberry; (/) underground stems— e.g., iris, potato, Solomon's seal, rhizomes of ferns. In examining the stems the following points should be noticed: (i) The nodes and iiiternodes, observing the length of the latter in different parts of the stem; (ii) the arrangement of leaves, which are so placed as not to shade each other (in the case of a plant like the privet notice the difference between the position of leaves on an upright shoot and that of leaves on a horizontal branch); (iii) in the case of twining stems notice the direction taken by the growing tip, whether from right to left or the opposite, (2.) Internal structure: Examine sections (both transverse and longitudinal) of stems of monocot3 7 iedonous plants such as maize, nikau palm, bamboo, or cane, and dicotyledonous trees such as oak, pine, &c, and notice the differences of structure. In the former note (a) the absence of a central core of pith, (b) the hard fibrous strands and soft surrounding tissue, (c) the hard outer rind ; in the latter observe (a) the pith, (6) the annual rings, (c) the medullary rays, (d) the thick bark. If sections of old trees are available, determine their age by counting the annual rings. (3.) Storage of food in underground stems: Examine the underground stems of the iris and Solomon's seal, the tubers of the artichoke and potato, and the conn of the gladiolus or crocus. Test these for starch by means of iodine-solution, and, if possible, microscopic sections. (4.) Compare new potato-tubers and those exhausted by sprouting. (5.) Conveyance of sap by stems : Water a well-developed sunflower or tomato-plant growing in a pot, and place it in a warm shaded situation for an hour. Then cut off the stem, and fasten a glass tube to the stump by means of a rubber tube. Now pour in a little water, tap the tube to displace air-bubbles, and mark the height at which the water stands in the tube. After a time notice the difference in height of the liquid in the tube. (6.) Healing of wounds: Examine places on trees where branches have been cut or broken off, and notice how the plant has endeavoured to repair the damage. Observe the difference between the results where branches have been cut off close to the stem, and where the branches have been allowed to project some distance beyond the bark. Make drawings of such cases. Experiments with Leaves. —(1.) Collect, mount on cards, and describe leaves of various shapes. Make drawings of typical leaves. (2.) Collect as many leaves as possible of the following