BULL. GEOL. SOC. AM. 



VOL. 28, 1916, PL. 24 



LIMESTONE FROM LANCASTER, WISCONSIN 



Tlic wiiito areas arc (loloDiilc. Iho darker onc^s calcite. Doloinilo is irregularly scat- 

 tered Willi reference to the beddiny-. The shape ot! the dolomitic patch in the lower 

 centi-al ])orlion suiiaests i-elationshi)! to au or.iianic sti'iu-tnre, possihly algal. The calcitic 

 l)orlioii is fossilil'erous. Fossils in dolomite '.wr sc'arce. This specimen, which is natural 

 size, was ol)tained from the hasal comiiaci iieds of (lalena formation at J. Wright's 

 (liiai-ry. Lancaster, Wisconsin. 



