28 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 148 



The most striking fossil is the Olenoides, unfortunately known only 

 from fragmentary pygidia. Notwithstanding the presence of this pre- 

 dominantly Middle Cambrian genus, the abundance of Ankoura and 

 Kormagnostus suggests about the same age as the red beds at the base 

 of the Nolichucky in the Rogersville area. 



Faunules collected from the Comby Ridge localities (end/ 10 =: 

 U.S.G.S. collection 2407, cne/10). Thorn Hill (cne/13), and Copper 

 Ridge (cne/12) yielded: 



Ankoura triangularis 

 Cedaria temiesseensis 

 Kormagnostus simplex 

 Menomonia, sp. undet. 

 Norwoodella halli 

 Norwoodella walcotti 



This faunule is presumably somewhat younger than any of those 

 of the Cedaria zone collected from the vicinity of Rogersville. 



FAUNA OF THE CREPICEPHALUS ZONE 



In all the sections studied, an unfossiliferous interval separates the 

 youngest observed faunule of the Cedaria zone from the oldest fossils 

 of the Crepicephalus zone. The lower and middle portions of the Noli- 

 chucky formation are in general sparingly fossiliferous, being repre- 

 sented either by shales with siltstone beds, or in part by the massive 

 lower limestone member. Only when either the shales contain fairly 

 pure, crystalline limestone layers, or the massive limestone is partly 

 replaced by a thin-bedded limestone, may well-preserved fossils be 

 expected. These conditions occur erratically at different localities, 

 hence a single section seldom supplies a succession of several faunules, 

 and it is difficult to place those collected in different areas in proper 

 stratigraphic order. In general, the beds of the Crepicephalus zone 

 become more fossiliferous upward, the richest in most sections being 

 those that just underlie the Aphelaspis zone. 



Probably the earliest fossils of the Crepicephalus zone collected in 

 the area are those from near the base of the lower limestone member 

 occurring in the vicinity of Rogersville (collections cnk/1, cnk/3). 

 The species include : 



*Blountia alexas 



Blountia montanensis 

 *Coosella planicauda 



Coosella, sp. undet. 

 *Crepicephalus convergens 



Dreshachia amata 

 *Kingstonia inflata 



Maryvillia arion 



