Origin of Leaves-The Growing-point: Aucuba, Common Laurel, Tulip Tree, Rose-Basipetal and Basifugal de- velopment Centaurea, Galium-Ocrea: The Plane, Poly- gonum-Vernation: Conduplicate, Plicate, Circinnate, Re- volute, Involute, Equitant, Convolute--Leaves of Water Delicacy of Young Leaves-Grew's Description-Position as- sumed by Buds-Diminution of Radiation-Darwin's Sug- gestion-Protection by Leaf-base, by Modified Leaves, by Leaf-stalk, by Stipules, by Connate Stipules, by Spines, by Hair, by Gum or Resin-Protection by Older Organs : Uvaria, St. John's Wort, Berberry--Protection by Leaf-stalk: Walnut, Box Elder, Sophora, Citharexylum, Rhus, Kalmia, Plane, Philadelphus (Syringa), Actinidia, Robinia, Broom, Whitebeam, Clematis-Protection by Stipules: Virginian Creeper, Pea, Lathyrus, Vine, Petteria, Guaiacum, Gardenia, Alstonia, Spergularia-Protection by Hairs: Polygonum amphibium, Viburnum, Horse Chestnut, Plane, Stachys, Nettle-Protection by Gum or Resin: Horse Chestnut, Poplar, Hazel Nut, Honeysuckle, Currant, Hornbeam, Whitebeam-Alder-Magnolia-Protection by the Leaf-base: Rose)-Protection by Leaf-stalk: Elder-Protection by Stip- ules: Leea, Pea, Hop, Virginian Creeper, Vine, Bucklandia, Passion Flower, Poplar, Lime, Birch, Beech, Hornbeam, Hazel Nut, Oak, Whitebeam-Protection by Connate Stip- Great Variety of Forms-Difference of Texture-Species with different Forms of Stipules: Hawthorn, Ribes, Quince, Poten- tilla, Nuttallia, Geum, Exochorda, Azara, Abutilon, Diplo- Stipules Performing Leaf Functions: Pansy, Galium, Acacia, Lathyrus Aphaca, Adesmia-Spinous Stipules: Robinia, Cap paris, Ribes oxyacanthoides, Bauhinia, Porlieria, Paliurus- Glandular Stipules: Viburnum, Psidium, Tropaeolum cilia- tum-As an Assistance in Climbing: Smilax, Paliurus australis-As Reserves of Nourishment: Gunnera-As Composition of Leaf: Leaf-base with Stipules; Leaf-stalk with dependent on the Leaf; (2) that they are independent organs; (3) that they are a constituent part of the LeafReasons for adopting the third view: Pansy, Galium, Plane, Polygonum-Tendrils- Monocotyledons -- Stipellæ -Stipules rare in Cotyledons-Composition of Leaf . CHAPTER IX SUMMARY PAGE 197 The Bud-Modes of Protection-Stipules: Nature of, Uses of— Fall of the Leaf: Not a case of Death, but a Vital Process; preparation for The Effect of Climate-Length of Life of Leaves-Pine-Spruce-Silver Fir-Yew-Pinsapo--Araucaria-Care taken by Nature to protect Buds-Conclusion. 223 INDEX 235 FIG. LIST OF ILLUSTRATIONS EXPLANATION OF THE PLATES PLATE I 1 Tilia vulgaris: Young Shoot. 2 The same, more advanced. 3 The same, with some of the Leaves expanded. 4 Carpinus Betulus: Young Shoot. 5 The same, to show the folding of the Leaves. 1 PLATE II At end of book Viburnum Opulus: Sprig with four opening Buds. 2 Acer platanoides: Young Shoot. 3 The same, more advanced. 4 The same, still further advanced. 5 Pyrus Aria: Sprig with three Buds. PLATE III At end of book 1 Ulmus montana: Young Shoot. 2 The same, more advanced. 3 The same, still more advanced. 4 The same, still further advanced. PLATE IV At end of book 1-6 Leaf-buds of Fagus sylvatica in different stages of develop ment. 7 Flower-bud of the same. 6 Young Leaves of Stachys sylvatica 7 Leaf of Plane, showing mode of protection of Young 8,9 Unopened Buds of Norway Maple 10 Young Shoot of Lime 11 Young Shoot of Hornbeam 12-14 Seed, Embryo and Seedling of Radish 678 11 12 13 21 Achimenes Haageana, showing growth of new Plant 19 16 16 20 23 23 24 Spiny Stipules of Robinia Pseud-Acacia. 36 Petteria ramentacea: Shoot in Spring 28 29 29 |