162 0. D. Walcott — Cambrian Fossils from Mt. Stephens, 



When comparing this fauna with one collected from the Mid- 

 dle Cambrian Terrane in Central Nevada, I found that several 

 of the species from the widely-separated localities were identi- 

 cal. This result led me to prepare the following notes, which 

 I now present to your consideration. 



The accompanying section is given to show the position of 

 the Mt. Stephens fauna in the Cambrian system, as observed in 

 the Highland range of Central Nevada, about 125 miles south 

 of Eureka.* 



Feet 



1. Dark reddish brown quartzite, evenly bedded and rip- 



ple-marked in some places * 350 



2. Bluish-gray limestone . _ 35 



Fossils : Olenellus Gilberti. 



3. Buff argillaceous and arenaceous shales, more or less 



solid near the base and laminated in the upper por- 

 tions 80 



Fossils : Annelid trails and fragments of Olenellus in 

 the lower part. Higher up, the heads of Olenellus 

 Gilberti and 0. Iddingsi occur in abundance. 



4. Light-colored gray limestone and bluish-black limestone 16 



5. Sandy, buff-colored shale _ 40 



Fossils : Annelid trails, Cruziana sp. ? 



,6. Dark bluish black limestone 46 



7. Finely laminated buff argillaceous shale 80 



Fossils : Hyolithes Billingsi and Ptychoparia Pio- 



chensis. 



8. Gray to bluish black compact limestone 18 



9. Buff arenaceous shales 64 



10. Compact cherty limestone . _ . 50 



11. Compact shaly sandstone in massive layers 40 



12. Hard siliceous gray limestone, almost quartz at base._ 12 



13. Yellow to buff sandy shale 70 



14. Bluish black limestone . 16 



15. Yellow to buff sandy shales 40 



16. Bluish black, hard, compact limestone.. 12 



Fragments of fossils, 



17. Shaly sandstone in massive layers 52 



1 8. Gray arenaceous limestone 2 



19. (a) Buff sandy shale ._ 40 



(b) Gray arenaceous limestone _ . _ _ 30 



(c) Sandy, calcareous shale __ 3 



73 



20. (a) Massive-bedded, bluish-gray limestone _ 200 



Fragments of fossils. 



(b) Compact gray siliceous limestone, almost 



quartzite in some places 400 



(c) Bluish black, evenly bedded limestone 6 



. 606 



Strike N. 30° W., dip 10° E. 



* U. S. Geol. Survey, Bull. No. 30, pp. 33, 34, 1886. 



