INDEX. 



Adams county, geology of 43 



Adams county, Quaternary system in 44 



Adams county, Coal Measures in 48 



Adams county, St. Louis limestone in . . 51 



Adams county, Keokuk limestone in 68 



Adams county, Burlington limestone in. . 55 



Adams county, Kinderhook group in 57 



Adams county, economical geology of. ... 58 



Adams county, soil and timber in 60 



Alethopteris 391 



Alethopteris crenulata 392 



Alethopteris cristata 395 



Alethopteris erosa 394 



Alethopteris emarginata 398 



Alethopteris falcata 396 



Alethopteris Hallii 394 



Alethopteris Hymenophylloides 393 



AJethopteris longifolia 469 



Alethopteris lanceolata .398 



Alethopteris Mazoniana 891 



Alethopteris muricata 395 



Alethopteris Pluckneti 895 



Alethopteris Pennsylvaniaca 469 



Alethopteris eolida 397 



Alethopteris spinulosa 396 



Amblipterus macropterus 348 



Annularia inflata 423 



Annularia longifolia 422 



Antliodus sarcululus 356 



Aphlebia 410 and 414 



Asterocarpus grandis 469 



Asteroptychius triangularis .... 370 



Asterophyllites grandis 424 



Asterophyllites foliosus 424 



Asterophyllites rigidus 424 



Asterophyllites tuberculatus 424 



Brown county, geology of 62 



Brown county, Quaternary system in 63 



PAGE. 



Brown county, Coal Measures in 66 



Brown county, St. Louis limestone in. ... 68 



Brown county, Keokuk group in 69 



Brown county, economical geology of. ... 70 

 Brown county, soil and agriculture 73 



Callipteris Sullivantii 468 



Carpolithes bullatus 463 



Carpolithes corticosus 462 



Carpolithes persicaria 462 



Cass and Menard counties, geology of. . . 163 

 Cass and Menard counties, Coal Measures 



in 165 



Cass and Menard counties, economical ge- 

 ology of 173 



Calhoun county, geology of. 1 



Calhoun county, St. Peters sandstone in . . 3 



Calhoun county, Trenton group in 4 



Calhoun county, Cincinnati group in 5 



Calhoun county, Niagara limestone in... . 6 



Calhoun county, Hamilton group in 8 



Calhoun county, Kinderhook group in .... 9 

 Calhoun county, Burlington limestone in. 12 



Calhoun county, Keokuk limestone in 14 



Calhoun county, St. Louis limestone in. . . 15 



Calhoun county, Coal Measures in 15 



Calhoun county, Quaternary system in. ... 17 

 Calhoun county, economical geology of. .. 18 

 Calhoun county, soil and agriculture of. . 22 



Cap au Ores, fault 2 



Caulopteris acantophora 458 



Caulopteris intermedia 459 



Caulopteris obtecta 467 



Champaign and Ford counties, geology of.. 272 



Chondrites Colletti 379 



Coal, analyses of. .33, 50, 58, 85, 86, 104, 



105, 257, 259, 316 



Coal shaft, Jacksonville 159 



Coal shaft, Bloomington 186 



