A completely new Upper Cambrian formational nomenclature is proposed for the southern Rocky Mountains of Alberta. The formations designated as Upper Cambrian are: Corona, and Mount Synge, Dresbachian; Bison Creek, Franconian; and the Mistaya, Trempealeauan. Two additional formations are referred to the Middle Cambrian sequence immediately underlying the Upper Cambrian; the Chephren and the Waterfowl. These latter formations were previously included in the Arctomys formation considered to be Upper Cambrian in age. The lowest Lower Ordovician formation is designated as the Howse River formation. In addition to the above mentioned new formations, the Arctomys, Sullivan, Lyell, Mons, Bosworth, Paget, Sherbrooke, Tangle Ridge, and Sabine formations are discussed in detail. All are considered obsolete, except the Sabine formation, the use of which, it is recommended, be confined to the Canal Flats area, British Columbia. The limits of the Upper Cambrian series in Alberta are more precisely determined, and tentative correlation of the Upper Cambrian of Alberta, Montana, and British Columbia is outlined. Trilobite faunas from all the Upper Cambrian zones, except the Crepicephalus zone, are described and illustrated. The Cedaria zone faunas contain fifteen genera and eighteen species, among them Bolaspidelia wellsvillensis, Nixonella montanensis, several species of Arapahoia and Cedarina, and Kingstonia mucro. Abundant topotype material of K. mucro has made redefinition of this species possible. The Aphelaspis zone is recognized by the discovery of Aphelaspis walcotti, and one questionable species of Aphelaspis. The Franconian zones are represented by Irvingella major, Taenicephalus shumardi, Parabolinoides cordiIlerensis, Maustonia nasota, KendalIina eryon, Ptychaspis striata, Prosaukia lonqicornis and Prosaukia curvicostata, to mention only the more important index species. The Saukia zone of the Trempealeauan is represented by species of Eurekia, StenopiIus, Bynumiella. Hardyia and IlIaenurus. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate