ILLINOIS STATE GEOLOGICAL SURVEY. MONOGRAPH No. 1. PLATE LXXX. 



* J 



1 2345 6 13 14 15 



J 



7 8 9 1O 11 12 



16 17 18 



19 2O 21 22 23 24 25 26 27 



31 32 33 34 35 36 28 29 3O 



> I 



37 38 39 4O 41 42 43 44 45 



46 



47 



48 



49 



5O 



51 



52 



53 57 



58 



54 



55 



56 



59 



6O 



61 62 63 64 65 66 



