CONTENTS. 



Page. 



Introduction 11 



History of the present botanical exploration of Alabama 11 



Plan of the present work 12 



Systematic arrangement 12 



Nomenclature 13 



History of the earlier botanical explorations of Alabama 13 



'William Bartram 13 



Samuel Botsford Buckley 16 



Hezekiah Gates 16 



Thomas Minott Peters 17 



Beaumont, Nevius, and recent collectors 17 



General physiographical features of the State 18 



Topography and geology 18 



The Coastal Plain '. 18 



Region of Crystalline Rocks * 19 



Region of the Coal Measures 20 



Region of the Coosa Valley 21 



Region of Tennessee Valley 21 



River system 22 



Tennessee River 22 



Alabama River 23 



Tombigbee River. 23 



Coosa River 24 



Cahaba River and smaller streams 24 



Climate 24 



Temperature .' 25 



Rainfall 26 



Winds ' -. 26 



Cloudiness 27 



General principles of the distribution of plants 28 



Plant zones of Humboldt, based on isothermal lines 28 



Life zones established by Merriam -. 29 



Boreal region 30 



Arctic or Arctic- Alpine zone 30 



Hudsonian zone 30 



Canadian zone 30 



Austral region 31 



Transition zone 31 



Upper Austral zone 31 



Lower Austral zone 32 



Tropical region 33 



Secondary factors influencing plant distribution 33 



Distribution of species as depending upon geological history 34 



7 



