II2 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 127 
S. incurvata (Shepard) = S. auburnensis Fenton 
Trematis huronensis ? Billings 
Zygospira recurvirostris (Hall) (not seen) 
The brachiopods recorded from the Ctenodonta bed are: 
Crania setigera Hall = Acanthocrania setigera (Hall) 
Lepiaena charlottae Winchell and Schuchert = Bellimurina charlottae (Winchell and 
Schuchert) 
Orthis tricenaria Conrad = Hesperorthis tricenaria (Conrad) 
Pholidops trentonensis minor Winchell and Schuchert = Craniops minor (Winchell and 
Schuchert) 
Plectambonites sericea Sowerby = Sowerbyella punctostriata (Mather) 
Strophomena incurvata (Shepard) = probably S. auburnensis Fenton 
Zygospira recurvirostris (Hall) 
Correlation of Guttenberg member.—The Guttenberg brings the first appear- 
ance in the Upper Mississippi Valley of Rafinesquina ss., Dalmanella ss., and 
the large Sowerbyella. The formation is correlated with the Oranda of the 
Appalachians and the Carters of West Tennessee. The Barnhart of Missouri is 
thought to be a southward extension of the Guttenberg. It is uncertain in the 
writer’s mind whether or not the Guttenberg is equivalent to lower Curdsville. 
That formation has the large Sowerbyella and early form of Rafinesquina. The 
Oranda is an earlier-deposited formation than the Curdsville and also contains 
large Sowerbyella and Rafinesquina. The Collierstown, probably the lateral 
equivalent of the Oranda, contains the Rafinesquina and other fossils to estab- 
lish this correlation. 
Ion member of Decorah formation —The 16 feet of shale and limestone form- 
ing the lon member at its type section passes into limestone to the south and into 
greenish shale to the north. In Minnesota this member includes the Phylloporina 
and fucoid beds. These contain the following brachiopods: 
Dinorthis sweeneyi (Winchell) 
Glyptorthis subcircularis Cooper 
Orthis tricenaria Conrad = Hesperorthis colet Cooper 
O. (Dalmanella) hamburgensis ? Walcott = D. winchelli Cooper 
O. (D.) testudinaria Dalman = Paucicrura rogata (Sardeson) 
O. (D.) subaequata circularis N. H. Winchell = Pionodema circularis (N. H. Winchell) 
O. (Hebertella) bellarugosa Conrad = Glyptorthis bellarugosa (Conrad) 
Pionodema minnesotensis Cooper 
P. uniplicata Cooper 
Plectambonites sericea Sowerby = Sowerbyella monilifera Cooper 
Rafinesquina alternata Conrad = R. trentonensis (Conrad) 
R. minnesotensis inquassa Sardeson = Opikina lirata Cooper 
Rhynchotrema inaequivalvis Castelnau = R. wisconsinense Fenton and Fenton 
Rostricellula colei Cooper 
Scenidium anthonensis Sardeson = Skenidioides anthonensis (Sardeson) 
Strophomena incurvata (Shepard) = S. musculosa Fenton 
S. septata Winchell and Schuchert 
S. trentonensis Winchell and Schuchert 
Zygospira recurvirostris (Hall) 
Correlation of Ion member.—Kay (1937, p. 294) correlates the lon member 
with the lower part of the Hull formation of Ontario, Quebec, and New York. 
