Fossils provide essential information for the determination of prior locations of the components of ancient orogenic belts such as the Appalachians. In this chapter we review the record of fossils from the Canadian Appalachians that, together with those from the Appalachians in the United States (Neuman et al., 1989), assist in determining the paleogeographic and tectonic evolution of this orogenic system. The rocks of the Canadian Appalachians are more fossiliferous than their counterparts in the United States because they are generally less deformed and metamor- phosed, and because there are important differences in the geology of the orogenic belt in the two countries.

Paleontological studies in Canada have long contributed to the development of ideas on the history of the orogen. The Cambrian faunas of the Avalon Zone in Newfoundland and Southern New Brunswick, and correlatives in north- western Europe were assigned by Walcott (1891) to an “Atlantic Coast Province”, considered by him to be diíferent from those of the “Appalachian Province” elsewhere in the Canadian and U.S. Appalachians. Following the introduc- tion of the idea of continental drift (Wegener, 1928), Grabau (1936) explained the similarity of the stratigraphy and faunas of eastern North America and northwestern Europe by deposition in contiguous synclines that were parts of his hypothetical “Pangea.” After the general acceptance of continental drift, Wilson (1966) proposed that a Paleozoic “proto-Atlantic Ocean” preceded the present Atlantic. In his view the Atlantic Cambrian faunas populated the eastern margin of the “proto-Atlantic Ocean”, contempora- neous Pacific faunas populated its