CONTENTS 



XI 



§ 54. Method of growth of roots 



§ 55. Absorbing and fixing organs of the lower plants 



§ 56. Absorbing and fixing organs of the ferns, mosses, 



liverworts 



§ 57. Method of fixation of the moulds and miishrooms 



and 



PAGE 



49 

 50 



50 

 51 



V. The Leaves 



§58. 

 §59. 

 §60. 

 §61. 

 §62. 

 §63. 

 §64. 

 §65. 

 §66. 

 §67. 

 §68. 

 §69. 

 §70. 

 §71. 

 §72. 



§73. 



§74. 

 §7.5. 

 §76. 

 §77. 

 §78. 

 §79. 

 §80. 

 §81. 

 §82. 

 §83. 

 §84. 

 §85. 



Absorption and fixation by the algae and bacteria 

 Structure of leaves 

 Leaves with both surfaces alike 

 Compound leaves 

 Composition of the air 

 Gases of use to the plant 

 Functions of the leaf . 

 The colors of leaves 

 Hidden chlorophyl 

 Characteristics of chlorophyl 

 Spectrum of chlorophyl 

 The leaf is a machine or mill 

 Quality of light most useful to the plant 

 Light destroys chlorophyl . 

 Light is necessary for the formation of chlorophyl in 

 instances ........ 



Capacity of leaves for the absorption of light , 

 Formation of food in chlorophyl-bearing organs 

 Non-green colors . 



Origin of red colors 



Changes in color . 



Autumnal colors . 



Uses of autumnal color 



Uses of red and other colors in flowers and fruits 



Characteristics of red and blue colors 



Red color as a shield .... 



Red color as a heat producer .... 



Red color as a heat saver 



Hairs as a protection to a leaf .... 



most 



52 

 54 

 56 

 56 

 57 

 57 

 58 

 58 

 59 

 60 

 60 

 61 

 61 

 62 



62 

 63 

 64 

 65 

 65 

 66 

 67 

 68 

 68 



70 

 71 



