VI. SEEDS AND SEEDLINGS 



EXERCISE PAGE 



57. Production of a Plant from a Seed 72 



58. Structure of a Seed 73 



59. Comparison of Seeds and Seedlings 74 



60. The Cotyledons . . 75 



61. A Monocotyledonous Seed 76 



VII. RELATION TO ENVIRONMENT 



62. What is the Effect of Different Temperatures on Germination ? 77 



63. What is the Effect of Gravity on the Growth of Root and Stem ? 79 



64. How do Stems and Leaves react to Light? 80 



65. Response to Touch 81 



66. Response of Tendrils 82 



67. Respiration . . . 83 



68. How much Force does the Wind exert against a Tree ? . . . 84 



69. Does the Bark assist in Strengthening the Stem ? 85 



70. Tensile Strength of Bark 86 



71. Competition between Branches, and Self-pruning 87 



72. In what Manner are Wounds in Trees Healed? 89 



73. What Precautions are Necessary in Transplanting Young Plants ? 91 



74. Transplanting Trees or Shrubs . 92 



VIII. RELATION OF SIMPLE PLANTS TO MAN'S LIFE 

 AND INDUSTRIES 



75. What are the Size, Shape, Motion, and General Appearance of 



Bacteria? 93 



76. To study the Growth and Distribution of Bacteria 95 



77. Physiology of Yeast . 98 



78. Structure of Yeast 100 



79. Preparation of Mold Cultures 101 



80. Bread Mold 102 



81. Detection of Molds in Air and in Other Places 103 



82. Blue Mold, or Blue Mildew 104 



83. Yellow Mold or Yellow Mildew 105 



84. Lilac Mildew a Parasitic Fungus 106 



85. Wheat Rust a Destructive Parasite 107 



86. Fungi which cause Plant Disease .' . . 109 



87. A Mushroom 110 



88 Wood-rotting Fungi Ill 



89. Classification of Fungi 112 



[ix] 



