Plant microfossils are extracted from strata of Upper Devonian age occurring at two previously uninvestigated localities in Eastern Canada and in the Canadian Arctic. The extraction procedure includes a new permanent palynological mounting technique using corn syrup and Permount, a synthetic resin. In addition, a method of eliminating by-product in residues after hydrofluoric acid, is also described. A number of miospore and acritarch form species are described and figured; nine new form species of miospores are proposed. The miospore species recovered from both localities indicate a geological age of early Upper Devonian (Frasnian) for the enclosing strata. A new way of assessing qualitative, regional palaeofloristic changes is provided by tabulation of morphological characteristics of individual miospores. The use of miospore species in defining Upper Devonian microfloral provinces and Upper Devonian-Lower Carboniferous migration of parent forms is demonstrated. / Thesis / Master of Science (MSc)