NO. 3 



UPPER CAMBRIAN TRILOBITE FAUNAS — RASETTI 



11 



Thickness 

 Feet Inches 



25. Siltstone, with thin Hmestone beds and lenses 2 



Collection cnt'VlS : 



Aphelaspis arsoides c 



Aphelaspis tumifrons cc 



Pseudagnostus communis r 



24. Shale 3 



23. Limestone : massive, one bed 1 



22. Shale 6 



21. Shale, with thin limestone beds 4 



Collection cns"/15, 2 feet above base : 



Aphelaspidella macropyge 



Aphelaspis rotundata 



Paraphelaspis vigilans 



20. Limestone : massive, one bed 2 



19. Shale, with thin-bedded limestone 5 



Collection cns'/15, from limestone lenses at middle 

 and top of interval : 



Aphelaspis arses r 



Aphelaspis rotundata c 



Paraphelaspis vigilans c 



18. Limestone : granular, one bed 1 



17. Siltstone 2 



16. Limestone : massive, granular 1 



15. Shale, with some thin siltstone and limestone beds 9 



Collection ens/ 15, 5 feet below top : 



Aphelaspis camiro c 



Aphelaspis laxa r 



Aphelaspis quadrata c 



Aphelaspis washburnensis r 



Aphelaspis, sp. undet. r 



14. Limestone conglomerate : one bed 



13. Shale, with a few thin limestone beds and lenses 10 



Collection cnr'/15, 2 feet below top : 



Aphelaspis laxa c 



12. Limestone : one bed, partly conglomerate 



1 1 . Shale, with a few, thin limestone beds 1 



Collection cnr/15, 8 inches below top : 



Aphelaspis zvalcotti cc 



Glaphyraspis declivis c 



Glaphyraspis oderi c 



10. Limestone : one bed of irregular thickness 



9. Shale 2 



8. Limestone : one bed of irregular thickness, partly conglomerate 1 



7. Shale, finely fissile 2 



6. Limestone : silty, granular, one bed 



5. Shale with thin siltstone and limestone beds, partly lenticular 4 



Collection cnq/15, 6 inches below top: 



Aphelaspis minor cc 



Glaphyraspis ornata r 



2-4 



6-7 



