NO. 3 UPPER CAMBRIAN TRILOBITE FAUNAS — RASETTI 21 



Collection cnn/17, in massive limestone beds 5-8 feet 

 below top : 

 Coosia, sp. undet. 

 Crepicephalns, sp. undet. 

 Tricrepicephalus, sp. undet. 



The section extends into lower beds of similar lithology, with alter- 

 nating massive and thin-bedded limestones and shale, the latter becom- 

 ing more prevalent downward. Occasional very fragmentary fossils 

 of the Crepicephalus zone were seen in this lower, unmeasured portion 

 of the section. 



This section, like the ones at Three Springs and Russell Gap, is 

 interesting for offering an Aphelaspis faunule a few feet above a 

 typical Crepicephalus zone faunule. The earliest Aphelaspis here is a 

 new species, A. transversa, closely related to A. buttsi and A. lata 

 which are the first to appear in the two above-mentioned sections. 



CLAIBORNE COUNTY 



Comby Ridge. — An interesting fossil locality occurs where U.S. 

 Route 25-E crosses Comby Ridge (Howard Quarter quadrangle). On 

 the E. side of the road and creek, the lower part of the Nolichucky 

 formation consists of shale with numerous limestone beds and lenses. 

 One such lens collected by Dr. Gunnar Henningsmoen and Dr. Robert 

 B. Neuman yielded fossils of the Cedaria zone, some of which are 

 illustrated herein. The author found further fossiliferous beds, in 

 addition to collecting from the above-mentioned lens. Unfortunately, 

 the exposures are poor and some of the fossiliferous lenses are weath- 

 ered out of the shale, hence their stratigraphic order is not always 

 certain. Lenses or beds believed to occur in ascending order were 

 labeled cnb/10, cnd/10, and cne/10. There is a considerable thickness 

 of shale underlying these fossiliferous beds but overlying the Mary- 

 ville limestone. 



The fossils are for the most part extremely fragmentary in a coarse- 

 grained calcarenite. The following faunules were observed. 



