BULL. GEOL. SOC. AM. 



MINNESOTA. 



VOL. 17, 1905, PL. 24 



/ooo 



6«\c rv o. 



S"k tt Koyo«.c- 



UreabocV. 



\Uuc\Wc 



TVcCcvrcOox 



TENNESSEE 



ILLINOIS. 



9° 



> /33 



35"' 



73' 



1 00 -"J 



Saint Petev 



5U n es"Rue ( 6ro, 



Clv\Un -L.st 



X^, Y\ o x 3} o V o Tm'\ K e. 



Represent!" n • ■ cambric and ordovicic series in southern Minnesota, Illinois, and Tennessee 



iSt0neSCharaC ^^ The Illinois section is from well records. 



