Smithsonian Report, 1 91 5,— Walcott. 



Plate 18. 



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DlKELOCEPHALIN/E: UPPER CAMBRIAN TRILOBITES. 



1. Dikdorephaliis minncsoknt'is Owen. From Goodhue County, Minn. 

 2-5, 5a. Saukia crass iinargittata (Whitfield). From Sauk County, Wis. 



