ILLUSTRATIONS 



PAGE 



Typical Leaf of Wavy- Leaved Aster 77 



Leaf of Large-Leaved Aster 80 



Leaves of Late-Flowering Aster 83 



Flowers of White Lettuce 86 



Leaf of Wild Peanut 91 



Purple Gerardia 95 



Leaf and Flowers of Ragweed 119 



Common Sow-Thistle 123 



Leaf Venation 126 



Stomata, Closed and Open 127 



Cell showing Nucleus and Protoplasm . . . . 129 



I 



