STE. GENEVIEVE FORMATION 
247 
Nucula? sp. 
Leda curta M. and W.? 
Pinna (species undetermined) 
Myalinaf sp. 
Myalina (species undetermined) 
Schizodkts (several undescribed 
species) 
Avioulopectdn (species undeter- 
mined) 
Allorisma (species undetermined) 
Leperditia (species undetermined) 
The limestone following the shale bears a fauna consisting 
almost entirely of brachiopods, the peleeypods so characteristic 
of the underlying shale being almost entirely wanting. The 
following list of species identified from a collection made from 
this bed as developed along Indian creek (Section II, bed 11) 
is representative: 
Rhombopora (species undeter- 
mined) 
Productus ovatus Hall 
Pugnoides ottumwa (White) 
Girtyella indianensis (Girty) 
Bpirifer pellaensis Weller 
Oomposita trinuclea (Hall)? 
Allorisma sp. 
Bellerophon sp. 
Phillipsiaf sp. 
Of the above forms Spirifer pellaensis ranks first in abun- 
dance, while Pugnoides ottumwa is a close second. 
A comparison of these Iowa collections with those which have 
been made from the typical exposures of the Ste. Genevieve 
limestone in Ste. Genevieve county, Missouri, and from expos- 
ures in Monroe county, Illinois, demonstrates the identity of 
the faunas. A number of the undetermined peleeypods of the 
Iowa collection are clearly undescribed, and are identical with 
species which have been collected in the Missouri and Illinois 
localities. As in Iowa, so in Illinois and Missouri, Pugnoides 
ottumwa is the most persistent index fossil of the fauna, and 
on the basis of these faunal resemblances the correlation of the 
Pella beds of Iowa with the Ste. Genevieve limestones may be 
considered as being fully established. 
Walker Museum, 
University of Chicago. 
