Contents 



PAGE 



Introduction xi 



The Topography and Hydrography of Illinois xv 



The Northwestern Unglaciated Area xvi 



The Areas of lowan and Illinoisan Drift xvii 



The Area of the Wisconsin Drift xix 



The Unglaciated Southern Area xx 



The River Systems xx 



Rock River System xxi 



Rock River xxi 



Pecatonica River xxiv 



Kishwaukee River xxv 



Green River xxv 



The Northwestern Area xxvi 



Galena River xxvii 



Apple River xxvii 



Plum River xxviii 



The Mississippi Bluff Drainage xxviii 



Edw^ards River xxviii 



Pope Creek xxix 



Henderson River xxix 



Bear Creek xxix 



Big Creek xxix 



Cahokia River xxx 



Illinois River System xxx 



Des Plaines River xxxi 



Kankakee River xxxiii 



Iroquois River xxxv 



Illinois River xxxv 



Fox River xliv 



Vermilion River xlv 



Mackinaw River xlvi 



Spoon River xlvii 



Sangamon River xlviii 



Salt Creek xlix 



Crooked Creek xlix 



Apple Creek 1 



Macoupin Creek li 



Kaskaskia River Svstem li 



Kaskaskia River Hi 



Shoal Creek liii 



Silver Creek liv 



Big Muddy River System liv 



