Palaeozoic Fossils of the Northwest — Bierbauer. 233 



•Preoccupied— see S. subcuspidatiformis S. A. Miller.— f/Zrici. 

 fPreoccupied- see S. subattenuata Hall. 

 JThis species does not occur in Minnesota.— JT". W. Sardeson. 

 gSee Orthisina americana Whitfield. 



II Meek regarded this identification of Geinitz's as founded on Productus nebraacensis 

 Owen.— WricZj. 



^Synonym for S. perplana Conrad. ' 



