284 /• ^- UDDEN 



varying from two to six inches. Evidently it was originally a 

 foraminiferal ooze, which has later been indurated by the infiltra- 

 tion and deposition of a strong calcareous matrix. 



The occurrence of such an ooze in the rocks of this age in 

 Iowa, in close association with great numbers of Fusulina cylin- 

 drica, is interesting as showing the luxuriance of the foraminiferal 

 fauna of the time, and also as furnishing an additional item for 

 consideration in correlating the uppermost members of the Car- 

 boniferous of America with those of Europe, where the same 

 forms occur at about the same level in the geological scale. A 

 full account of the other fossils of these beds will be published 

 in the next volume of the annual reports of the Iowa Geological 

 Survey. They represent the uppermost strata of the coal- 

 measures in the state. It may not be amiss in this connection to 

 record the fact that the author some years ago observed related, 

 if not identical, foraminifera in the higher strata of the coal- 

 measures at La Salle in Illinois. 



Some of the material from Iowa was forwarded to Professor 

 E. Schellwien, of Konigsberg, Germany, for exact identification, 

 and I take the liberty to quote from his reply as follows: 



Das zugesandte stlick kalk enthalt ganz besonders haufig die kleinen 

 schalchen von Ammodisciden und zwar einmal von Ammodiscus s. str., 

 dann aber noch haufiger von unregelmassig aufgerollten formen von A7nmo- 

 discus, welche ahnlich gestaltet sind, wie Am. inversus und die ebenso wie 

 dieser zur untergattung Psammophis gehoren. Derartige formen sind bisher 



nur im Obercarbon (hohere schichten desselben) gefunden Derselbe 



kalk enthalt ausserdem eine kleine Endothyra, welche ebenfalls am ehesten 

 mit einer vorwiegend im Obercarbon beobachteten aber auch im Untercarbon 

 auftretenden art, Endothyra parva Moll., iibereinstimmt. 



J. A. Udden. 



