658 E. O. ULRICH REVISION OF THE PALEOZOIC SYSTEMS 



Nittany dolomite (new) 



10. Massive, light gray, finely crystalline dolomite. An outcrop 

 out of tbe direct line of the section, but thought to be of 

 this bed, contained an Eccyliopterus like E. triangulus 

 Whitfield 198 



9. Alternating beds of light and dark gray, crystalline dolomite 



in beds of medium thickness 313 



8. Gray crystalline dolomites with some chert and a little sand- 

 stone. The chert is sparingly fossiliferous, the fossils 

 poorly preserved, those noted being slender gastropods of 

 the type of Hormotoma artemesia. The chert in this bed 

 increases rapidly in abundance in a southerly direction 

 from Bellefonte 132 



7. Mainly thick-bedded, in part probably slightly calcareous dolo- 

 mite, varying in color from light to medium shades of gray, 

 and in texture from distinctly crystalline to very compact. 

 The latter are brittle, sometimes resembling chert, and in 

 one such bed good molds of Ophileta coniplanata Whit- 

 field (?Vanuxem) and Sijntrophia cf. lateralis were ob- 

 served. Some chert in the residual mantle which, like that 

 of the overlying bed, grows more abundant to the south. 

 4 to 8 inch balls of Cryptzooii steeli not uncommon with 

 the chert 624 



Feet 



Total thickness of Nittany dolomite "^ 1,26T 



StoneJienge limestone 



Feet 



6. Dark gray, compact or vsubcrystalline. often oolitic pure lime- 

 stone, mottled with light colored, slightly magnesian lime- 

 stone. Highly and characteristically fossiliferous. Among 

 the more abundant species are Asaphus n. sp. (near A. 

 canaUs (Whitfield) but shorter). Riheiria calciferaf, R. 

 parva, EccyUomphalus multiseptarius. Bucania triplal, 



and Dalmanellal tvemplei 27 



5. Light gray, mainly compact, nearly pure limestone 70 



4. Magnesian limestone chiefly 40 



3. Gray, nearly pure, generally rather massive limestone with 

 occasional layers containing a small gastropod resembling 

 Ophileta levata and Holopea raymonclia. About (perhaps 



more than ) 390 



Covered, about 50 



2. Beds of thin argillaceous, fine-grained limestone alternating 



with thicker-bedded limestones 50 



»3 The thickness of the beds of this formation are as given by Collie (op. cit. p. 411),. 

 the present writer having neglected to measure them separately. Together they gave a 

 thickness of about 1,215 feet, or about 50 feet less than the aggregate of Collie's meas- 

 urements. 



