C. R. Stauffer — The Minnesota Devonian. 405 



Devonian (Cedar Valley limestone) 

 3. Limestone, gray to buff, massive to thin bedded, it 

 contains an abundance of a few fossil forms — 



Athyris fultonensis (Swallow) (aa) 



Atrypa reticularis (Linnaeus) (r) 



Murchisonia sp. (r) 



4' 0" 



2. Limestone, gray to buff, or brown, rough, hard, 

 and massive. Fossils very abundant in some 

 layers but limited to one form 



Atrypa reticularis (Linnaeus) (aa) 



10' 6" 



1. Limestone, gray to brown in color, partly covered, 



to the level of Cedar River 6' 0" 



It is quite impossible to present a complete section of 

 the Minnesota Devonian at the present time. In fact it 

 may never be possible to complete it satisfactorily unless 

 at some future time the region should be drilled for water 

 or other natural resources that may seem worth while. 

 But it may be pieced together, from scattered outcrops 

 and other information in somewhat the following manner. 



General Section of the Minnesota Devonian. 

 Devonian (Cedar Valley limestone) Thickness 



9. Limestone, buff to brown, massive, coarse, fossili- 



ferous. These are the beds exposed along the 



river just west of Lyle 20' 6" 



8. Limestone, blue to brown, argillaceous, forming the 



cement beds south of Austin 30' 0" 



7. Covered interval 10' ±0" 



6. Limestone, gray to white, compact, fine-grained, 



often alternating with coarser brown beds .. . 22' 0" 



5. Covered interval 12'±0" 



4. Limestone, brown, brecciated, with no fossils 6' 0" 



3. Limestone, gray to buff, massive, f ossilif erous . ... 10' 0" 

 2. Limestone, gray to brown, massive, full of corals 



and stromatoporoids 3' 0" 



1. Limestone, buff , massive, abundantly f ossilif erous . 20' 0" 



It is noticeable that all portions of this section are not 

 equally fossiliferous and that the fauna is not uniform 



