Marylaxd Geological Survey 149 



feet thickness 



Drab limestone banded with fine brown lines. Hackle-toothed 

 bedding planes. Orthoceras of. riyidium. Tcntaculites gyracan- 



thus, and Schuchertella prolifica (a) 284.5 7.4 286.2 



Yellow shale 2.0 278.8 



Massive, drab, banded limestone weathering into a prominent 



ridge 7.0 276.8 



Drab, banded limestone; fairly massive; upper surface ripple- 

 marked 5.0 269.8 



Platy, banded, medium-bedded limestone 4.5 264.8 



Platy, banded limestone weathering lower than the adjacent 



units 2.5 260.3 



Heavy-bedded, drab banded limestone, weathering platy. 



Tcntaculites gyracanthus and Ostracoda 254.8, 256 3.0 257.8 



Stromatopora bed. Stromatopora constellata 2.5 254.8 



Drab banded limestone 0.8 252.3 



Massive cobbly bed, full of Stromatoporoids including Stro- 

 matopora constellata. Stands out as a prominent ledge. Under 

 surface very irregular and with large nodules. Favosites hel- 



derbergice var. prwcedens 2.3 251.5 



Drab, banded limestone 3.0 249.2 



Stromatopora reef, Leperditia altoides (a) at top 1.2 246.2 



Irregular, very argillaceous limestone 0.8 245.0 



Massive light-gray limestone. Stromatopora reef 234-236. 

 Leperditia gigantea abundant 233.5, 234.5. Stromatopora con- 

 stellata, Cyathophyllum schucherti 240 16.5 244.2 



Thin-bedded and cobbly gray limestone with numerous stro- 

 matoporoids 5.5 227.7 



Two massive Stromatopora beds. Stromatopora constellata, 

 Favosites helderiergiw var. pnecedens and Cyathophyllum 



schucherti 217-218 6.1 222.2 



Thin to medium-bedded gray limestone. Stromatopora 20d A. 9.2 216.1 



Cobbly gray limestone 1.2 206.9 



Thin-bedded, gray limestone, very cherty in the upper part 



and becoming less so towards the base 8.3 205.7 



Massive gray limestone 5.2 197.4 



Massive argillaceous gray limestone; upper 2 feet rather 



cherty ^ 9.8 192.2 



Gray limestone interbedded -with white chert, the latter mak- 

 ing up much of the thickness of the unit 5.5 182.4 



Massive, cobbly argillaceous gray limestone. A single narrow 

 chert layer near the top. At the base occurs Diplostenopora 



siluriana 5.5 176.9 



Shale weathered to clay 0.9 171.4 



