178 The American Geologist. March, 1891 
fact that it contains few or no organic remains. It is apparently 
homogeneous throughout, consisting of thin, hard, evenly bedded 
flaggy layers which are very noticeably micaceous. 
From the so-called ban-en shales of the Warren section Prof. 
Hall cites Tropidocaris interrupta and "fragments of the shells of 
Spirifera disjuncta," while the corresponding beds in the Panama 
section are ' ' totally barren of fossils of an}' kind — as far as 
observed." 
U. S. Geological Survey, December, 1890. 
THE ROCKS AT ST. PAUL, INDIANA, AND VICINITY. 
Charles S. Beachler, Crawfordsville, Ind. 
The rocks at St. Paul, Indiana, exposed along the small stream 
known as Flat Rock, may be described as an arm two or three 
miles wide, extending in length for about fifteen miles, in a south- 
westerly direction from the main belt of Upper Silurian rocks. 
This arm may readily be referred, b} T its fossils, to the Niagara 
group ; its exposure being a result of the eroding away of the 
thin Upper Helderberg stratum of limestone overlying it, while 
the streams have cut their channels through the rocks, thus giv- 
ing a section of the entire strata of the Niagara group in this state. 
The rocks are covered with Devonian dirt which has been carried 
a short distance from the north-east, as seen by the glacial mark- 
ings on the underlying rocks ; the fossils found in the dirt, Favosites 
forbesi Hall, Atrypa reticularis Linn., are in a perfect state of 
preservation and show no marks of their transportation — so they 
could not have been carried very far. 
A section of the rocks at St. Paul may be taken as a t}^pical 
section of the rocks of this group in this state, as it exhibits four 
well marked strata as follows ; 
Drift, Devonian dirt, containing Devonian corals and brackio- 
pods. 
No. 5. Upper Helderberg limestone overlying Niagara. 
No. 4. Blue shale (Tbe Waldron fossil beds, 10 feet). Seen on Mill 
creek, a short distance above the point where it flows into 
Flat Bock. 
No. 3. Thinly laminated limestone, thickness 15 feet: containing 
Pi&ocrinus gemmiformte 6. A. Miller; P. globosus Rintrueberg; 
