CONTENTS 

 PART I 



PAGE 



PREFACE v 



I. MOSSES AND LICHENS AT HOME 3 



II. How TO KNOW THE LICHENS AND MOSSES AND WHAT 

 THEY ARE DOING ON ROCKS AND TREES 



General comparison of Mosses and Lichens . 8 



Poets' conception of Mosses and Lichens . . 9 



Scientists' conception of Mosses and Lichens . 1 1 



Soil makers 12 



corroding rock 12 



decomposing vegetable matter . . . 12 



reclaiming marshes 15 



Marsh-building on Mt. Marcy . . . . 17 



Mosses which build up limestone . . . 17 



III. LICHENS IN HISTORY 



Mention by early Greek philosophers . . 19 



Use in dye industry 19 



Use as drugs 20 



Use as food 20 



IV. THE ORIGIN AND NATURE OF LICHENS 



Spontaneous generation 22 



Dual nature 22 



The fungus partner 22 



The alga partner 23 



Experiments in artificial production of lichens . 24 



How a lichen is made 24 



Free fungus spore with free algal cell . . 24 



Classification of algae associated . . . 25 



Classification of fungi associated . . 25 



Interest to the collector ..... 26 



External beauty and form . . . . 26 



Absorbing power of water . . . . 27 



vii 



