RAYMOND: CORRELATION OF THE ORDOVICIAN STRATA. 241 



position of the Ottosee in relation to the other formations is that given 

 by Bassler (98) from outcrops on Walker Mountain north of Marion, 

 Smyth Co., Virginia. The strata there named " Holston marble and 

 associated strata" were later named Ottosee by Ulrich. 



Feet. 

 Sevier shale. , 



Brown to olive and gray shales. 1500 



Moccasin limestone. 



Impure, argillaceous limestone. 300 



Ottosee formation. 



(e) Unfossiliferous drab shales. 40 



(d) Nodular limestone and yellowish to gray shales 



holding many Bryozoa. 30 



(c) Massive gray and pink marble with numerous 



Bryozoa, Solenopora and Stylaraea parva. 30 



(b) Clayey nodular limestone and shale. Some of the 



layers are crowded with Receptaculites. 50 



(a) Massive crystalline limestone. 40 



Athens shale. 



Dark to black shale with black slaty limestone at the 



base. Linguloids and trilobites are abundant at the 



base. 500 ± 



Stones River formation. 170 



Knox dolomite (Beekmantown in age). 



The Stones River of this section is stated by Bassler to contain in its 

 upper part a typical Chazy fauna, though the only species mentioned 

 are Maclurites magnus and Stylaraea parva. 



The trilobites mentioned as occurring in the Athens are not listed, 

 but it is known that this formation in at least two places in Virginia 

 carries the Neuiagraptus gracilis (Normanskill) fauna. (See p. 234). 



From the Ottosee Bassler lists Echinosphaerites, Batostoma sevieri, 

 Scetiellopora radiata, Diaholocrinus vesperalis, Solenopora compada, 

 and Receptaculites biconstrictus. It is quite true that this fauna is 

 somewhat unlike that of the Echinosphaerites zone in the other 

 localities, but there is nothing in the composition of the fauna 

 itself to indicate that it is older than Black River. Receptaculites 

 biconsirictus is similar to the Black River R. occidentalis, which occurs 

 with Echinosphaerites at Chambersburg and Belief onte. Pa., Batos- 

 toma is principally a Black River genus, and the other fossils of the 

 Ottosee have a rather indefinite value in correlation. 



